Simplify handling of GitRepo status resources

[aruiz14]

Summary

Change how the GitRepo status info is obtained and processed, by consuming the new fields exposed by Fleet.

Occurred changes and/or fixed issues

Fixes #13243

• Depends on Simplify PerClusterState and include all states and cluster IDs fleet#3287

Technical notes summary

This PR changes (again, see #12896) the way that bundles state is processed, by iterating over the list of bundles, for simplicity.
Also:

• It uses the new PerClusterResourceCounts status field
• Uses the new format for Resources.perClusterState in order to build the GitRepo's resource table, getting rid of BundleDeployments altogether.

Areas or cases that should be tested

Areas which could experience regressions

There is a small regression in the Resources table for GitRepos, since the info backing the Age column is no longer available. However, this field was often blank as it's not always available.

Screenshot/Video

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