chore: Update discovery artifacts (#1386)

## Deleted keys were detected in the following stable discovery artifacts:
admin directory_v1 https://github.com/googleapis/google-api-python-client/commit/7bac81fc588ccbe7b5e6c75af52b719e73efd118
doubleclickbidmanager v1.1 https://github.com/googleapis/google-api-python-client/commit/895ff465e58dffd1f6e29dffd673418c76007e1b

## Discovery Artifact Change Summary:
feat(adexchangebuyer): update the api https://github.com/googleapis/google-api-python-client/commit/3cf7a8dceb567f3c89c307f3496c381af91b0fc6
feat(admin): update the api https://github.com/googleapis/google-api-python-client/commit/7bac81fc588ccbe7b5e6c75af52b719e73efd118
feat(content): update the api https://github.com/googleapis/google-api-python-client/commit/aab557d6c59a5c414d0ac0bc6349763523c9816f
feat(dfareporting): update the api https://github.com/googleapis/google-api-python-client/commit/c83912bec60626d3388fbe749d7a395fa3bc6c22
feat(doubleclickbidmanager): update the api https://github.com/googleapis/google-api-python-client/commit/895ff465e58dffd1f6e29dffd673418c76007e1b
feat(servicecontrol): update the api https://github.com/googleapis/google-api-python-client/commit/facd7ecc18c129cf8010d19d3969e8d5b4598dfc
diff --git a/googleapiclient/discovery_cache/documents/adexchangebuyer2.v2beta1.json b/googleapiclient/discovery_cache/documents/adexchangebuyer2.v2beta1.json
index 6b056d9..9a2942e 100644
--- a/googleapiclient/discovery_cache/documents/adexchangebuyer2.v2beta1.json
+++ b/googleapiclient/discovery_cache/documents/adexchangebuyer2.v2beta1.json
@@ -2568,7 +2568,7 @@
       }
     }
   },
-  "revision": "20210526",
+  "revision": "20210527",
   "rootUrl": "https://adexchangebuyer.googleapis.com/",
   "schemas": {
     "AbsoluteDateRange": {
@@ -4404,7 +4404,9 @@
             "DAY",
             "WEEK",
             "MONTH",
-            "LIFETIME"
+            "LIFETIME",
+            "POD",
+            "STREAM"
           ],
           "enumDescriptions": [
             "A placeholder for an undefined time unit type. This just indicates the variable with this value hasn't been initialized.",
@@ -4413,7 +4415,9 @@
             "Day",
             "Week",
             "Month",
-            "Lifetime"
+            "Lifetime",
+            "Pod",
+            "Stream"
           ],
           "type": "string"
         }