Fix tooltip jumping behavior when closing FTB

Summary

When closing the File Tree Browser (FTB), tooltips exhibit unexpected behavior by jumping to the top of the screen before disappearing, creating a jarring user experience.

Steps to reproduce

  1. Navigate to any repository page with the repositoryFileTreeBrowser feature flag enabled
  2. Open the File Tree Browser
  3. Hover over an element with a tooltip within the FTB
  4. Close the File Tree Browser while the tooltip is visible
  5. Observe the tooltip behavior

Related issues/MRs

#582189 (comment 2929325785)

!217853 (comment 2990869929)

Edited by Alyssa Trinh