message: build: ignore go-control-plane mirror git commit error code
diff: @@ -97,7 +97,7 @@ def publishGoProtobufs(repo, sha):
  git(repo, 'config', 'user.name', USER_NAME)
  git(repo, 'config', 'user.email', USER_EMAIL)
  git(repo, 'add', 'envoy')
  - git(repo, 'commit', '-s', '-m', MIRROR_MSG + sha)
  + git(repo, 'commit', '--allow-empty', '-s', '-m', MIRROR_MSG + sha)
  git(repo, 'push', 'origin', BRANCH)
  