message: Add details to the Azure Core beta 6 changelog
  Reviewed the commits since the last release:
diff: ### Breaking Changes
  -- Remove `Context::CancelWhen()`.
  +- Removed `Context::CancelWhen()`.
  - Removed `LogClassification` and related functionality, added `LogLevel` instead.
  ### Bug Fixes
  - Fixed computation of the token expiration time in `BearerTokenAuthenticationPolicy`.
  +- Fixed compilation dependency issue for MacOS when consuming the SDK from VcPkg.
  +- Fixed support for sending requests to endpoints with a custom port within the url on Windows when using the WinHttp transport.
  ## 1.0.0-beta.5 (2021-02-02)
  