message: Upgrade nanopb to latest release.
  Fixes security vulnerability reported in
diff: @@ -576,12 +576,12 @@ def tf_repositories(path_prefix = "", tf_repo_name = ""):
  tf_http_archive(
  name = "com_github_nanopb_nanopb",
  - sha256 = "8bbbb1e78d4ddb0a1919276924ab10d11b631df48b657d960e0c795a25515735",
  + sha256 = "18234d9f01b57248472a9bfa65c3379352b5d66c15b0ef1c2b4feece4b5670fe",
  build_file = "@com_github_grpc_grpc//third_party:nanopb.BUILD",
  - strip_prefix = "nanopb-f8ac463766281625ad710900479130c7fcb4d63b",
  + strip_prefix = "nanopb-0.4.1",
  urls = [
  - "https://storage.googleapis.com/mirror.tensorflow.org/github.com/nanopb/nanopb/archive/f8ac463766281625ad710900479130c7fcb4d63b.tar.gz",
  - "https://github.com/nanopb/nanopb/archive/f8ac463766281625ad710900479130c7fcb4d63b.tar.gz",
  + "https://storage.googleapis.com/mirror.tensorflow.org/github.com/nanopb/nanopb/archive/0.4.1.tar.gz",
  + "https://github.com/nanopb/nanopb/archive/0.4.1.tar.gz",
  ],
  )
  