Filter entities in the UI (part 5): Add snapshot tests for the blueprint tree

[abey79]

Related

• Part of Project: filtering entities in the UI (first iteration) #8586
• Part of a series of PR:
  • Filter entities in the UI (part 0): Make CustomContent more useful #8645
  • Filter entities in the UI (part 1): Introduce a filter widget #8652
  • Filter entities in the UI (part 2): Introduce entity filtering in the time panel #8654
  • Filter entities in the UI (part 3): Move action to a menu in the blueprint panel and keep default blueprint when using heuristics #8672
  • Filter entities in the UI (part 4): Add entity filtering in the blueprint tree #8706
  • Filter entities in the UI (part 5): Add snapshot tests for the blueprint tree #8728
  • …

What

This PR adds snapshot tests for the blueprint tree. It includes several improvements to the testing rig, such that those test are now quite compact.

TODO

•  update graphview tests accordingly

[github-actions]

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Result	Commit	Link	Manifest
✅	5ee40e0	https://rerun.io/viewer/pr/8728	+nightly +main

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