Change gz-collections.yaml spec to support ci configs

[j-rivero]

The PR should not change any existing code but reforms the yaml spec to define how the libs and ci interacts:

• 872d0df modifies the yaml to include a ci_configs section that can host all related CI details and the different collections only reference them by name. Names are equal to Ubuntu distributions but could be something different.
• eb54989 modifies gazebo_libs by doing some changes:
  • generate_ciconfigs_by_lib is a parse step that builds an index of ci-configurations supported by each lib. It should help to avoid extra parsing in the diffferent jobs creation.
  • generate_label_by_requirements handles the label selection for the jobs, nvidia or large-memory.
  • The code is not handling the exclude section in ci
  • Rest of the changes are just to adapt the job creation iteration to the new index.

I would not expect any XML code change with the exception of gz-harmonic repo removal since now we are excluding it.

[j-rivero]

Oh ignition_collection needs to be migrated, back to draft.

[j-rivero]

Oh ignition_collection needs to be migrated, back to draft.

ok, ready. CI says that there is no contect change in any job or any new job.

[j-rivero]

There is no change in the final XML configurations according to CI, I'm going to merge the PR to create new ones.