message: Update link to chromium modern c++ page
  The page was renamed in
  No-Try: true
  Cr-Commit-Position: refs/heads/main@{#35783}
diff: @@ -28,7 +28,7 @@ WebRTC is written in C++17, but with some restrictions:
  * We only allow the subset of C++17 that is also valid C++20; otherwise, users
  would not be able to compile WebRTC in C++20 mode.
  -[chr-style-cpp]: https://chromium.googlesource.com/chromium/src/+/main/styleguide/c++/c++11.md
  +[chr-style-cpp]: https://chromium.googlesource.com/chromium/src/+/main/styleguide/c++/c++-features.md
  Unlike the Chromium and Google C++ style guides, we do not allow C++20-style
  designated initializers, because we want to stay compatible with compilers that
  @@ -146,7 +146,7 @@ In most cases, one will want to explicitly control lifetimes, and therefore use
  exist both from the API users and internally, with no way to invalidate pointers
  held by the API user, `rtc::scoped_refptr` can be appropriate.
  -[chr-std-shared-ptr]: https://chromium.googlesource.com/chromium/src/+/main/styleguide/c++/c++11.md#shared-pointers-banned
  +[chr-std-shared-ptr]: https://chromium.googlesource.com/chromium/src/+/main/styleguide/c++/c++-features.md#shared-pointers-banned
  ### `std::bind`
  