remove legacy code

Author: ohmayr

.github/sync-repo-settings.yaml

@@ -11,14 +11,6 @@ branchProtectionRules:
     # No Kokoro:  the following are Github actions
     - 'lint'
     - 'mypy'
-    - 'unit_grpc_gcp-3.7'
-    - 'unit_grpc_gcp-3.8'
-    - 'unit_grpc_gcp-3.9'
-    - 'unit_grpc_gcp-3.10'
-    - 'unit_grpc_gcp-3.11'
-    - 'unit_grpc_gcp-3.12'
-    - 'unit_grpc_gcp-3.13'
-    - 'unit_grpc_gcp-3.14'
     - 'unit-3.7'
     - 'unit-3.8'
     - 'unit-3.9'

noxfile.py

@@ -36,7 +36,6 @@
 # 'docfx' is excluded since it only needs to run in 'docs-presubmit'
 nox.options.sessions = [
     "unit",
-    "unit_grpc_gcp",
     "unit_wo_grpc",
     "unit_w_prerelease_deps",
     "unit_w_async_rest_extra",