Use gz-cmake5

[scpeters]

🎉 New feature

Part of #1309

Summary

This increases the version of gz-cmake used by gz-tools3 to gz-cmake5. This change is being made before the mass change to remove version numbers from package names so that the script will work properly for this package.

Test it

Check CI

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• 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)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.