chore: Update discovery artifacts (#1410)

## Deleted keys were detected in the following stable discovery artifacts:
managedidentities v1 https://github.com/googleapis/google-api-python-client/commit/e96adbb1ba3e4e56d916cc28474f85543f17ad0e

## Discovery Artifact Change Summary:
feat(appengine): update the api https://github.com/googleapis/google-api-python-client/commit/ffcf86035a751e98a763c8a2d54b70d3a55ca14d
feat(containeranalysis): update the api https://github.com/googleapis/google-api-python-client/commit/9a1c70b7df3e074fc9fbd0eebdaf75a91046078c
feat(documentai): update the api https://github.com/googleapis/google-api-python-client/commit/07a6e774ac185442a99437896eaee774946b5846
feat(drive): update the api https://github.com/googleapis/google-api-python-client/commit/773910fdf25b084aa3623d24fe99c8a1330fbecb
feat(managedidentities): update the api https://github.com/googleapis/google-api-python-client/commit/e96adbb1ba3e4e56d916cc28474f85543f17ad0e
feat(spanner): update the api https://github.com/googleapis/google-api-python-client/commit/87da2f3605ec1b8986324cddc33f2b5601d3e896
diff --git a/googleapiclient/discovery_cache/documents/run.v1alpha1.json b/googleapiclient/discovery_cache/documents/run.v1alpha1.json
index c1f84d1..a21db56 100644
--- a/googleapiclient/discovery_cache/documents/run.v1alpha1.json
+++ b/googleapiclient/discovery_cache/documents/run.v1alpha1.json
@@ -268,7 +268,7 @@
       }
     }
   },
-  "revision": "20210528",
+  "revision": "20210604",
   "rootUrl": "https://run.googleapis.com/",
   "schemas": {
     "Capabilities": {
@@ -816,7 +816,7 @@
       "id": "JobSpec",
       "properties": {
         "activeDeadlineSeconds": {
-          "description": "Optional. Specifies the duration in seconds relative to the startTime that the job may be active before the system tries to terminate it. If set to zero, the system will never attempt to terminate the job based on time. Otherwise, the value must be positive integer. +optional",
+          "description": "Optional. Not supported. Specifies the duration in seconds relative to the startTime that the job may be active before the system tries to terminate it. If set to zero, the system will never attempt to terminate the job based on time. Otherwise, the value must be positive integer. +optional",
           "format": "int64",
           "type": "string"
         },
@@ -840,7 +840,7 @@
           "description": "Optional. Describes the instance that will be created when executing a job."
         },
         "ttlSecondsAfterFinished": {
-          "description": "Optional. ttlSecondsAfterFinished limits the lifetime of a Job that has finished execution (either Complete or Failed). If this field is set, ttlSecondsAfterFinished after the Job finishes, it is eligible to be automatically deleted. When the Job is being deleted, its lifecycle guarantees (e.g. finalizers) will be honored. If this field is set to zero, the Job won't be automatically deleted. +optional",
+          "description": "Optional. Not supported. ttlSecondsAfterFinished limits the lifetime of a Job that has finished execution (either Complete or Failed). If this field is set, ttlSecondsAfterFinished after the Job finishes, it is eligible to be automatically deleted. When the Job is being deleted, its lifecycle guarantees (e.g. finalizers) will be honored. If this field is set to zero, the Job won't be automatically deleted. +optional",
           "format": "int32",
           "type": "integer"
         }