chore(bazel): update protobuf to v3.21.3 (#182)

* chore(bazel): update protobuf to v3.21.3

chore(bazel): update gax-java to 2.18.4

PiperOrigin-RevId: 463115700

Source-Link: googleapis/googleapis@52130a9

Source-Link: googleapis/googleapis-gen@6a4d9d9
Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiNmE0ZDlkOWJiM2FmYjIwYjBmNWZhNGY1ZDlmNjc0MGIxZDBlYjE5YSJ9

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: Anthonios Partheniou <partheniou@google.com>

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/domain_mappings/async_client.py

@@ -601,9 +601,6 @@ async def sample_delete_domain_mapping():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         request = appengine.DeleteDomainMappingRequest(request)

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/domain_mappings/client.py

@@ -810,9 +810,6 @@ def sample_delete_domain_mapping():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         # Minor optimization to avoid making a copy if the user passes

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/instances/async_client.py

@@ -434,9 +434,6 @@ async def sample_delete_instance():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         request = appengine.DeleteInstanceRequest(request)

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/instances/client.py

@@ -667,9 +667,6 @@ def sample_delete_instance():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         # Minor optimization to avoid making a copy if the user passes

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/services/async_client.py

@@ -516,9 +516,6 @@ async def sample_delete_service():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         request = appengine.DeleteServiceRequest(request)

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/services/client.py

@@ -730,9 +730,6 @@ def sample_delete_service():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         # Minor optimization to avoid making a copy if the user passes

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/versions/async_client.py

@@ -624,9 +624,6 @@ async def sample_delete_version():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         request = appengine.DeleteVersionRequest(request)

packages/google-cloud-appengine-admin/google/cloud/appengine_admin_v1/services/versions/client.py

@@ -839,9 +839,6 @@ def sample_delete_version():
 
                       }
 
-                   The JSON representation for Empty is empty JSON
-                   object {}.
-
         """
         # Create or coerce a protobuf request object.
         # Minor optimization to avoid making a copy if the user passes