message: Fix Authors Check presubmit.
  Adding the account that performs the auto-update of the WebRTC version
  string.
  No-Presubmit: True
  No-Try: True
  Cr-Commit-Position: refs/heads/master@{#32830}
diff: @@ -975,7 +975,8 @@ def CommonChecks(input_api, output_api):
  input_api,
  output_api,
  bot_allowlist=[
  - 'chromium-webrtc-autoroll@webrtc-ci.iam.gserviceaccount.com'
  + 'chromium-webrtc-autoroll@webrtc-ci.iam.gserviceaccount.com',
  + 'webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com',
  ]))
  results.extend(
  input_api.canned_checks.CheckChangeTodoHasOwner(
  