Limit usage of GitHub Actions Annotations

[carlocab]

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew typecheck with your changes locally?
• Have you successfully run brew tests with your changes locally?

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• only use annotations for opoo and onoe if
  HOMEBREW_GITHUB_ACTIONS is set. This will make using brew less
  noisy in GitHub Actions for third parties. See
  Please use github action annotations only for high priority warnings discussions#5602.
• if we've already called puts_annotation_if_env_set, then we no
  longer need to print the message to $stderr. The message from the
  annotation already show up in the GitHub Actions log, so printing to
  $stderr just leads to duplicate messages in the log.

While we're here, let's make sure to forward the file: and line:
kwargs of puts_annotation_if_env_set to the Annotation constructor.

[MikeMcQuaid]

As noted in #18340 (comment): would rather we instead fixed the warnings here (like #18330) rather than making them only apply to our CI.