message: tools: strengthen v2 API package regexes in proto_build_targets_gen.py.
  Some weak regexes were causing v4alpha protos to end up in the v2 docs
  in this PR fixes.
diff: @@ -15,8 +15,8 @@ V2_REGEXES = list(
  map(re.compile, [
  r'envoy[\w\.]*\.(v1alpha\d?|v1)',
  r'envoy[\w\.]*\.(v2alpha\d?|v2)',
  - r'envoy\.type\.matcher',
  - r'envoy\.type',
  + r'envoy\.type\.matcher$',
  + r'envoy\.type$',
  r'envoy\.config\.cluster\.redis',
  r'envoy\.config\.retry\.previous_priorities',
  ]))
  