message: tools: include .m/.mm files when formatting
  Including these file types will allow this script to be reused in other repos like Envoy Mobile for linting.
  Risk Level: Low
  Testing: Locally
  Docs Changes: No
diff: @@ -17,7 +17,8 @@ import traceback
  EXCLUDED_PREFIXES = ("./generated/", "./thirdparty/", "./build", "./.git/", "./bazel-", "./.cache",
  "./source/extensions/extensions_build_config.bzl",
  "./tools/testdata/check_format/", "./tools/pyformat/")
  -SUFFIXES = (".cc", ".h", "BUILD", "WORKSPACE", ".bzl", ".java", ".md", ".rst", ".proto")
  +SUFFIXES = ("BUILD", "WORKSPACE", ".bzl", ".cc", ".h", ".java", ".m", ".md", ".mm", ".proto",
  + ".rst")
  DOCS_SUFFIX = (".md", ".rst")
  PROTO_SUFFIX = (".proto")
  