docs: Add documentation for enums (#284)

* docs: Add documentation for enums

fix: Add context manager return types

chore: Update gapic-generator-python to v1.8.1
PiperOrigin-RevId: 503210727

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packages/google-cloud-bigquery-connection/google/cloud/bigquery_connection_v1/services/connection_service/client.py

@@ -1457,7 +1457,7 @@ def sample_test_iam_permissions():
         # Done; return the response.
         return response
 
-    def __enter__(self):
+    def __enter__(self) -> "ConnectionServiceClient":
         return self
 
     def __exit__(self, type, value, traceback):

packages/google-cloud-bigquery-connection/google/cloud/bigquery_connection_v1/types/connection.py

@@ -318,7 +318,16 @@ class CloudSqlProperties(proto.Message):
     """
 
     class DatabaseType(proto.Enum):
-        r"""Supported Cloud SQL database types."""
+        r"""Supported Cloud SQL database types.
+
+        Values:
+            DATABASE_TYPE_UNSPECIFIED (0):
+                Unspecified database type.
+            POSTGRES (1):
+                Cloud SQL for PostgreSQL.
+            MYSQL (2):
+                Cloud SQL for MySQL.
+        """
         DATABASE_TYPE_UNSPECIFIED = 0
         POSTGRES = 1
         MYSQL = 2

packages/google-cloud-bigquery-connection/samples/generated_samples/snippet_metadata_google.cloud.bigquery.connection.v1.json

@@ -8,7 +8,7 @@
     ],
     "language": "PYTHON",
     "name": "google-cloud-bigquery-connection",
-    "version": "1.9.0"
+    "version": "0.1.0"
   },
   "snippets": [
     {