chore: Update discovery artifacts (#1486)

## Deleted keys were detected in the following stable discovery artifacts:
displayvideo v1 https://github.com/googleapis/google-api-python-client/commit/21f81c824089d0060dbd624f9755eea554464af2
sts v1 https://github.com/googleapis/google-api-python-client/commit/a8ebc2bef5d0ff6c449d65fcc9c0554c1f388985

## Deleted keys were detected in the following pre-stable discovery artifacts:
networkconnectivity v1alpha1 https://github.com/googleapis/google-api-python-client/commit/68588ad4744aa3c7a3a0afa12a1566f54ab3be94

## Discovery Artifact Change Summary:
feat(apigee): update the api https://github.com/googleapis/google-api-python-client/commit/41ae79b3554ffc9f1622e44757751009eeed76f8
feat(bigqueryreservation): update the api https://github.com/googleapis/google-api-python-client/commit/b0483aba20b17580b400283fb0073f07715bf254
feat(chat): update the api https://github.com/googleapis/google-api-python-client/commit/270312294f1cf89041825b0f31bfcf872fda9854
feat(cloudbuild): update the api https://github.com/googleapis/google-api-python-client/commit/30c122278e75a99b5b2a6ed330f317015134a23d
feat(cloudscheduler): update the api https://github.com/googleapis/google-api-python-client/commit/0405b1db79fe87305be25ba4f9389e94490040a7
feat(contactcenterinsights): update the api https://github.com/googleapis/google-api-python-client/commit/3abcf5334053f5612fd79163f2c433e5793ee782
feat(dialogflow): update the api https://github.com/googleapis/google-api-python-client/commit/c4935840495b1487d4be47b63f6c416113b9413f
feat(displayvideo): update the api https://github.com/googleapis/google-api-python-client/commit/21f81c824089d0060dbd624f9755eea554464af2
feat(monitoring): update the api https://github.com/googleapis/google-api-python-client/commit/d997b2c0d13203ac29b55c19858ef375380a5b7b
feat(networkconnectivity): update the api https://github.com/googleapis/google-api-python-client/commit/68588ad4744aa3c7a3a0afa12a1566f54ab3be94
feat(notebooks): update the api https://github.com/googleapis/google-api-python-client/commit/b975c34568f62bbf19f67f4731fe091aeeda8a75
feat(retail): update the api https://github.com/googleapis/google-api-python-client/commit/c2bcb7081a4f656b9e136ea38637cf262b60f387
feat(servicenetworking): update the api https://github.com/googleapis/google-api-python-client/commit/3bdc7b9d0854918ef65ccb4a3798d2f3f3b19d70
feat(sts): update the api https://github.com/googleapis/google-api-python-client/commit/a8ebc2bef5d0ff6c449d65fcc9c0554c1f388985
diff --git a/googleapiclient/discovery_cache/documents/dns.v1.json b/googleapiclient/discovery_cache/documents/dns.v1.json
index 4ec025f..36f1ff5 100644
--- a/googleapiclient/discovery_cache/documents/dns.v1.json
+++ b/googleapiclient/discovery_cache/documents/dns.v1.json
@@ -3,10 +3,10 @@
     "oauth2": {
       "scopes": {
         "https://www.googleapis.com/auth/cloud-platform": {
-          "description": "See, edit, configure, and delete your Google Cloud Platform data"
+          "description": "See, edit, configure, and delete your Google Cloud data and see the email address for your Google Account."
         },
         "https://www.googleapis.com/auth/cloud-platform.read-only": {
-          "description": "View your data across Google Cloud Platform services"
+          "description": "View your data across Google Cloud services and see the email address of your Google Account"
         },
         "https://www.googleapis.com/auth/ndev.clouddns.readonly": {
           "description": "View your DNS records hosted by Google Cloud DNS"
@@ -1235,7 +1235,7 @@
       }
     }
   },
-  "revision": "20210728",
+  "revision": "20210809",
   "rootUrl": "https://dns.googleapis.com/",
   "schemas": {
     "Change": {