[RUN AS-IF-FOSS] Move cluster_health to core

What does this MR do?

This moves all of the cluster_health frontend and qa files from EE to Core

#208224 (closed)

Note: There's no changelog for this as there's another pending MR to move the backend files to core

!35610 (merged)

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content