Transition utils to use bzlmod to build

[mjcarroll]

bzlmod is the new external dependency management system for bazel https://docs.bazel.build/versions/main/bzlmod.html)

This migrates gz-utils to use bzlmod via rules_gazebo.

[codecov]

Codecov Report

Attention: Patch coverage is 22.36842% with 59 lines in your changes missing coverage. Please review.

Project coverage is 72.26%. Comparing base (3838ce6) to head (9d95231).
Report is 17 commits behind head on main.

Files with missing lines	Patch %	Lines
log/src/Logger.cc	0.00%	43 Missing ⚠️
log/src/SplitSink.cc	44.82%	16 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #128      +/-   ##
==========================================
- Coverage   81.79%   72.26%   -9.53%     
==========================================
  Files           8       11       +3     
  Lines         401      476      +75     
==========================================
+ Hits          328      344      +16     
- Misses         73      132      +59     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.