Annotation for objects referenced in composite snapshots

[georgweiss]

Adds an annotation icon to snapshots and composite snapshots if referenced in at least one composite snapshot. This helps user determine that a snapshot or composite snapshot cannot be deleted.

Documentation updated with new screenshots.

Checklist

• Testing:

  • The feature has automated tests
  • [ X] Tests were run

• Documentation:

  • [ X] The feature is documented
  • [X ] The documentation is up to date
  • Release notes:
    • Added an entry if the change is breaking or significant
    • Added an entry when adding a new feature