Use gz-utils test macros

[chapulina]

• Part of Deprecate utilities in favor of ign-utils gz-cmake#171

Summary

The utilities from gz-cmake are deprecated.

Checklist

• Signed all commits for DCO
• 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)
• 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.

🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸🔸

[codecov]

Codecov Report

Merging #624 (8188792) into ign-rendering6 (8afbc05) will not change coverage.
The diff coverage is n/a.

❗ Current head 8188792 differs from pull request most recent head 321cc5d. Consider uploading reports for the commit 321cc5d to get more accurate results

@@               Coverage Diff               @@
##           ign-rendering6     #624   +/-   ##
===============================================
  Coverage           80.00%   80.00%           
===============================================
  Files                   1        1           
  Lines                  15       15           
===============================================
  Hits                   12       12           
  Misses                  3        3           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8afbc05...321cc5d. Read the comment docs.