Use gz-rotary-sdformat in macos workflow

[scpeters]

🦟 Bug fix

Fixes incorrect dependency versions in macos workflow

Summary

The macos workflow has started failing recently for pull requests targeting the main branch (see #1691 and #1693).

The macos workflow currently uses a hardcoded PACKAGE variable to encode the homebrew formula name whose dependencies should be installed. The main branch is still using the Jetty formula sdformat16, so this should be updated to gz-rotary-sdformat, which also avoids needing to specify the number.

Backport Policy

• This is safe to backport to the following versions:
  • Jetty
  • Ionic
  • Harmonic
  • Fortress
• This should not be backported
• I am not sure
• Other (fill in yourself)

Checklist

• Signed all commits for DCO
• Added a screen capture or video to the PR description that demonstrates the fix (as needed)
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• Updated Bazel files (if adding new files). Created an issue otherwise.
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