chore: Update discovery artifacts (#1450)

## Deleted keys were detected in the following stable discovery artifacts:
chat v1 https://github.com/googleapis/google-api-python-client/commit/8e39e1ef5482735fbaaed3be74ee472cf44cd941
dns v1 https://github.com/googleapis/google-api-python-client/commit/e2ba913fc51f78ce4b9fb6f9de97f61bd35cd356

## Deleted keys were detected in the following pre-stable discovery artifacts:
dns v1beta2 https://github.com/googleapis/google-api-python-client/commit/e2ba913fc51f78ce4b9fb6f9de97f61bd35cd356

## Discovery Artifact Change Summary:
feat(analyticsadmin): update the api https://github.com/googleapis/google-api-python-client/commit/a2e2d768e5412072ef11891ae7fb9145e2c4693d
feat(androiddeviceprovisioning): update the api https://github.com/googleapis/google-api-python-client/commit/83151f4ebd2992a53f815133304d8cb2c72d50c5
feat(chat): update the api https://github.com/googleapis/google-api-python-client/commit/8e39e1ef5482735fbaaed3be74ee472cf44cd941
feat(cloudasset): update the api https://github.com/googleapis/google-api-python-client/commit/ebd9b97ec74f0f257ccb4833f747f88d02075926
feat(cloudfunctions): update the api https://github.com/googleapis/google-api-python-client/commit/06332af99b1b1a9894bf4f553e014936225761de
feat(cloudsearch): update the api https://github.com/googleapis/google-api-python-client/commit/4aab6137bb350cb841a6b48fd37df67a209ba031
feat(content): update the api https://github.com/googleapis/google-api-python-client/commit/c65f297a775687fbfcbae827f892fc996a3d1ab1
feat(datacatalog): update the api https://github.com/googleapis/google-api-python-client/commit/af28eef0b37a5d0bb3a299f9fd9740b63f9e23bd
feat(dns): update the api https://github.com/googleapis/google-api-python-client/commit/e2ba913fc51f78ce4b9fb6f9de97f61bd35cd356
feat(documentai): update the api https://github.com/googleapis/google-api-python-client/commit/d1b9df7ee0a041d4cf632a77a626764c37e72889
feat(file): update the api https://github.com/googleapis/google-api-python-client/commit/0cd6277980d02363e3d609901d12d62b594adc92
feat(firebaseappcheck): update the api https://github.com/googleapis/google-api-python-client/commit/f8c39017aa392c0930ab79cdf7f828fe1e97e313
feat(firebasestorage): update the api https://github.com/googleapis/google-api-python-client/commit/66b6961871fea5b1a41a5b8359d7f76d6e390386
feat(gameservices): update the api https://github.com/googleapis/google-api-python-client/commit/31fd4dc22bd1e615caeafc22482caad65bbd55e9
feat(gkehub): update the api https://github.com/googleapis/google-api-python-client/commit/58ae34d8dfb4a7827b4f56e99fd48dedc64b4364
feat(ml): update the api https://github.com/googleapis/google-api-python-client/commit/15e0de32f2ea94d6ed3e0c18cd6e59cc239b37e7
feat(monitoring): update the api https://github.com/googleapis/google-api-python-client/commit/2b52d9ff5341caec20577538c0c4eaf83a896651
feat(notebooks): update the api https://github.com/googleapis/google-api-python-client/commit/c4698a84e526ab47710d2bde22827b337f2f480c
feat(people): update the api https://github.com/googleapis/google-api-python-client/commit/a646e56d40f2c7df40f48d42442c1941fc1c6674
feat(recommender): update the api https://github.com/googleapis/google-api-python-client/commit/ef997b0293c0e075208c7af15fa4e9bd6f29e883
feat(secretmanager): update the api https://github.com/googleapis/google-api-python-client/commit/489541e760eae9745724eb8cad74007903dd4f5b
feat(spanner): update the api https://github.com/googleapis/google-api-python-client/commit/acdb8fccfbb9f243f06dfff68d61cee2e58c9e45
feat(testing): update the api https://github.com/googleapis/google-api-python-client/commit/e2bde192a3e20ebd00995185cd92b47a086be8d9
diff --git a/googleapiclient/discovery_cache/documents/recommender.v1beta1.json b/googleapiclient/discovery_cache/documents/recommender.v1beta1.json
index ce8b919..c4f32a6 100644
--- a/googleapiclient/discovery_cache/documents/recommender.v1beta1.json
+++ b/googleapiclient/discovery_cache/documents/recommender.v1beta1.json
@@ -1178,7 +1178,7 @@
       }
     }
   },
-  "revision": "20210625",
+  "revision": "20210709",
   "rootUrl": "https://recommender.googleapis.com/",
   "schemas": {
     "GoogleCloudRecommenderV1beta1CostProjection": {
@@ -1623,6 +1623,14 @@
             "$ref": "GoogleCloudRecommenderV1beta1OperationGroup"
           },
           "type": "array"
+        },
+        "overview": {
+          "additionalProperties": {
+            "description": "Properties of the object.",
+            "type": "any"
+          },
+          "description": "Condensed overview information about the recommendation.",
+          "type": "object"
         }
       },
       "type": "object"