chore: Update discovery artifacts (#1328)

## Deleted keys were detected in the following stable discovery artifacts:
admindirectoryv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/1feda6f78f168e28d7842f49ad91fb00dc24ec19)
bigqueryreservationv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/7e6c78d448e472caaa67971160fdd44ccce061b0)
computev1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/131a5cd5bda8512217aa461042b33fb287790839)
doubleclickbidmanagerv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/d20e7e2553a1ea5d3690afba366683d4eb0ca647)
doubleclickbidmanagerv11[ [More details]](https://github.com/googleapis/google-api-python-client/commit/d20e7e2553a1ea5d3690afba366683d4eb0ca647)
serviceconsumermanagementv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/864ef4795a0e89263859f493f9c40d1a85e90c28)
serviceusagev1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/ecd65a89c54132856b47747439faf901dbfbafcb)

## Deleted keys were detected in the following pre-stable discovery artifacts:
bigqueryreservationv1beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/7e6c78d448e472caaa67971160fdd44ccce061b0)
computealpha[ [More details]](https://github.com/googleapis/google-api-python-client/commit/131a5cd5bda8512217aa461042b33fb287790839)
computebeta[ [More details]](https://github.com/googleapis/google-api-python-client/commit/131a5cd5bda8512217aa461042b33fb287790839)
serviceconsumermanagementv1beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/864ef4795a0e89263859f493f9c40d1a85e90c28)
serviceusagev1beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/ecd65a89c54132856b47747439faf901dbfbafcb)

## Discovery Artifact Change Summary:
admindirectoryv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/1feda6f78f168e28d7842f49ad91fb00dc24ec19)
bigqueryreservationv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/7e6c78d448e472caaa67971160fdd44ccce061b0)
bigqueryreservationv1beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/7e6c78d448e472caaa67971160fdd44ccce061b0)
computealpha[ [More details]](https://github.com/googleapis/google-api-python-client/commit/131a5cd5bda8512217aa461042b33fb287790839)
computebeta[ [More details]](https://github.com/googleapis/google-api-python-client/commit/131a5cd5bda8512217aa461042b33fb287790839)
computev1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/131a5cd5bda8512217aa461042b33fb287790839)
containerv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/9bc4a12e7ab57a1b5a5d3637087b80b3008e3352)
containerv1beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/9bc4a12e7ab57a1b5a5d3637087b80b3008e3352)
doubleclickbidmanagerv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/d20e7e2553a1ea5d3690afba366683d4eb0ca647)
doubleclickbidmanagerv11[ [More details]](https://github.com/googleapis/google-api-python-client/commit/d20e7e2553a1ea5d3690afba366683d4eb0ca647)
serviceconsumermanagementv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/864ef4795a0e89263859f493f9c40d1a85e90c28)
serviceconsumermanagementv1beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/864ef4795a0e89263859f493f9c40d1a85e90c28)
serviceusagev1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/ecd65a89c54132856b47747439faf901dbfbafcb)
serviceusagev1beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/ecd65a89c54132856b47747439faf901dbfbafcb)
diff --git a/googleapiclient/discovery_cache/documents/serviceusage.v1.json b/googleapiclient/discovery_cache/documents/serviceusage.v1.json
index 3b07fc9..fd1ffef 100644
--- a/googleapiclient/discovery_cache/documents/serviceusage.v1.json
+++ b/googleapiclient/discovery_cache/documents/serviceusage.v1.json
@@ -426,7 +426,7 @@
       }
     }
   },
-  "revision": "20210426",
+  "revision": "20210427",
   "rootUrl": "https://serviceusage.googleapis.com/",
   "schemas": {
     "AdminQuotaPolicy": {
@@ -1057,13 +1057,6 @@
       "description": "`Endpoint` describes a network endpoint of a service that serves a set of APIs. It is commonly known as a service endpoint. A service may expose any number of service endpoints, and all service endpoints share the same service definition, such as quota limits and monitoring metrics. Example service configuration: name: library-example.googleapis.com endpoints: # Below entry makes 'google.example.library.v1.Library' # API be served from endpoint address library-example.googleapis.com. # It also allows HTTP OPTIONS calls to be passed to the backend, for # it to decide whether the subsequent cross-origin request is # allowed to proceed. - name: library-example.googleapis.com allow_cors: true",
       "id": "Endpoint",
       "properties": {
-        "aliases": {
-          "description": "Unimplemented. Dot not use. DEPRECATED: This field is no longer supported. Instead of using aliases, please specify multiple google.api.Endpoint for each of the intended aliases. Additional names that this endpoint will be hosted on.",
-          "items": {
-            "type": "string"
-          },
-          "type": "array"
-        },
         "allowCors": {
           "description": "Allowing [CORS](https://en.wikipedia.org/wiki/Cross-origin_resource_sharing), aka cross-domain traffic, would allow the backends served from this endpoint to receive and respond to HTTP OPTIONS requests. The response will be used by the browser to determine whether the subsequent cross-origin request is allowed to proceed.",
           "type": "boolean"
@@ -1279,7 +1272,7 @@
       "type": "object"
     },
     "GoogleApiService": {
-      "description": "`Service` is the root object of Google service configuration schema. It describes basic information about a service, such as the name and the title, and delegates other aspects to sub-sections. Each sub-section is either a proto message or a repeated proto message that configures a specific aspect, such as auth. See each proto message definition for details. Example: type: google.api.Service name: calendar.googleapis.com title: Google Calendar API apis: - name: google.calendar.v3.Calendar authentication: providers: - id: google_calendar_auth jwks_uri: https://www.googleapis.com/oauth2/v1/certs issuer: https://securetoken.google.com rules: - selector: \"*\" requirements: provider_id: google_calendar_auth",
+      "description": "`Service` is the root object of Google API service configuration (service config). It describes the basic information about a logical service, such as the service name and the user-facing title, and delegates other aspects to sub-sections. Each sub-section is either a proto message or a repeated proto message that configures a specific aspect, such as auth. For more information, see each proto message definition. Example: type: google.api.Service name: calendar.googleapis.com title: Google Calendar API apis: - name: google.calendar.v3.Calendar visibility: rules: - selector: \"google.calendar.v3.*\" restriction: PREVIEW backend: rules: - selector: \"google.calendar.v3.*\" address: calendar.example.com authentication: providers: - id: google_calendar_auth jwks_uri: https://www.googleapis.com/oauth2/v1/certs issuer: https://securetoken.google.com rules: - selector: \"*\" requirements: provider_id: google_calendar_auth",
       "id": "GoogleApiService",
       "properties": {
         "apis": {