Use matching branch in CI from infrastructure repositories

[scpeters]

CI is challenging for PRs that bump version dependencies because they require changes to infrastructure repositories like the following:

• https://github.com/ignition-tooling/gazebodistro
• https://github.com/ignition-tooling/gzdev
• https://github.com/ignition-tooling/release-tools
• https://github.com/osrf/homebrew-simulation

In practice, we often merge the infrastructure PRs first to allow CI to work in the library PR then try to merge the library PR as quickly as possible because other pull requests will be broken. I think we could simplify this by changing our -ci-pr_any- builds to check if the library branch name matches a branch name in these infrastructure repositories and use the matching name if so. We could also consider requiring a special string in the branch name (like branch_match) to avoid false positives.

[scpeters]

A first attempt at this for gzdev is in #572

[scpeters]

brew CI should be handled by #575

[scpeters]

• Try to checkout matching gzdev branch for PR jobs #572
• Brew CI: try checking out matching branches #575
• Use matching gzdev branch in https://github.com/ignition-tooling/action-ignition-ci Ubuntu builds
  • Try checking out ci_matching_branch for gzdev action-gz-ci#46
  • Cherry-pick #46 to focal: Try checking out ci_matching_branch for gzdev action-gz-ci#47
• Use matching homebrew-simulation branch in macOS workflow builds
  • Bumps in garden: use ign-math7 gazebosim/sdformat#803
  • Try to checkout matching branch in macos workflow gazebosim/gz-common#286
• Use matching gazebodistro branch in Windows builds Add python tool to check for matching CI branches #583