chore: Update discovery artifacts (#1325)

## Deleted keys were detected in the following stable discovery artifacts:
apigeev1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/9106808da3e03faa4c27913358e0c07edd82ff5a)

## Discovery Artifact Change Summary:
apigeev1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/9106808da3e03faa4c27913358e0c07edd82ff5a)
dataflowv1b3[ [More details]](https://github.com/googleapis/google-api-python-client/commit/9dd646184e70a83831f3347fc01a3eb0090ca0e8)
dialogflowv2[ [More details]](https://github.com/googleapis/google-api-python-client/commit/a7f2e96e6b283771e986d9ec7f1f057ff67e2a29)
dialogflowv2beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/a7f2e96e6b283771e986d9ec7f1f057ff67e2a29)
dialogflowv3[ [More details]](https://github.com/googleapis/google-api-python-client/commit/a7f2e96e6b283771e986d9ec7f1f057ff67e2a29)
documentaiv1beta3[ [More details]](https://github.com/googleapis/google-api-python-client/commit/ee1318d36230ff4b7393ce1f15d6a9ee71d23cea)
healthcarev1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/1204c1d486e08630773812ff1cc35843d98eb1d8)

feat(apigee): update the api
feat(dataflow): update the api
feat(dialogflow): update the api
feat(documentai): update the api
feat(healthcare): update the api

diff --git a/googleapiclient/discovery_cache/documents/calendar.v3.json b/googleapiclient/discovery_cache/documents/calendar.v3.json
index 4a1e7e4..9c2f827 100644
--- a/googleapiclient/discovery_cache/documents/calendar.v3.json
+++ b/googleapiclient/discovery_cache/documents/calendar.v3.json
@@ -1723,7 +1723,7 @@
       }
     }
   },
-  "revision": "20210417",
+  "revision": "20210424",
   "rootUrl": "https://www.googleapis.com/",
   "schemas": {
     "Acl": {
@@ -2074,9 +2074,9 @@
         "calendar": {
           "additionalProperties": {
             "$ref": "ColorDefinition",
-            "description": "A calendar color defintion."
+            "description": "A calendar color definition."
           },
-          "description": "A global palette of calendar colors, mapping from the color ID to its definition. A calendarListEntry resource refers to one of these color IDs in its color field. Read-only.",
+          "description": "A global palette of calendar colors, mapping from the color ID to its definition. A calendarListEntry resource refers to one of these color IDs in its colorId field. Read-only.",
           "type": "object"
         },
         "event": {
@@ -2084,7 +2084,7 @@
             "$ref": "ColorDefinition",
             "description": "An event color definition."
           },
-          "description": "A global palette of event colors, mapping from the color ID to its definition. An event resource may refer to one of these color IDs in its color field. Read-only.",
+          "description": "A global palette of event colors, mapping from the color ID to its definition. An event resource may refer to one of these color IDs in its colorId field. Read-only.",
           "type": "object"
         },
         "kind": {