15765 fleet re introduce cluster groups selector for target clusters

[marcelofukumoto]

Summary

Fixes #15765

Occurred changes and/or fixed issues

Added previous option of having cluster group to the App Bundles on Fleet.
shell/assets/translations/en-us.yaml Changed some structure and added new labels for the cluster group
shell/components/fleet/FleetClusterTargets/index.vue Main file to be changed, added the Cluster Group options. Grouped the Label and Name together into Clusters.
shell/components/fleet/tests/FleetClusterTargets.test.ts Test file created
shell/utils/tests/fleet.test.ts Changed test to allow ClusterGroup as "clusters" instead of "advanced"
shell/utils/fleet.ts Changed to remove clusterGroup from the "advanced" option and added to "clusters"

Bug found: There is a bug going back and forth on the page resets the Target part. It resets after the second back and forth.

Technical notes summary

Previously ClusterGroup and Name were not added together. On this implementation it is added together and seems to be working.
ClusterGroupSelector still considered as an "advanced" case.
The control of the Cluster in the list is done by the utils/fleet.ts so that has not changed.
Most of the logic has been copied from the old code to avoid any problems and added to the current code.

Areas or cases that should be tested

• Create, edit and view of the App Bundle

Areas which could experience regressions

• Create, edit and view of the App Bundle
• Changed to the fleet.ts for the target could affect other places, but the "mode" added is an already used one "clusters"

Screenshot/Video

• I will prepare the test case files and add here.
• Follow some screenshots for now
  View:

Edit:
Empty State:

Selected:

Checklist

• The PR is linked to an issue and the linked issue has a Milestone, or no issue is needed
• The PR has a Milestone
• The PR template has been filled out
• The PR has been self reviewed
• The PR has a reviewer assigned
• The PR has automated tests or clear instructions for manual tests and the linked issue has appropriate QA labels, or tests are not needed
• The PR has reviewed with UX and tested in light and dark mode, or there are no UX changes
• The PR has been reviewed in terms of Accessibility
• The PR has considered, and if applicable tested with, the three Global Roles Admin, Standard User and User Base