message: Update Boost.ASIO to use std::string_view on macOS
diff: @@ -23,7 +23,10 @@ cc_library(
  "BOOST_THREAD_VERSION=4",
  "BOOST_THREAD_PROVIDES_EXECUTORS",
  "BOOST_ALL_NO_LIB",
  - ],
  + ] + select({
  + "@toolchain//:macos_x86_64": ["BOOST_ASIO_HAS_STD_STRING_VIEW"],
  + "//conditions:default": [],
  + }),
  includes = ["."],
  )
  