[Manual backport 2.x] [discover] Query editor UI clean up (#7896)

[abbyhu2000]

Description

Manual backport of #7896

Issues Resolved

Screenshot

Testing the changes

Changelog

Check List

• All tests pass
  • yarn test:jest
  • yarn test:jest_integration
• New functionality includes testing.
• New functionality has been documented.
• Update CHANGELOG.md
• Commits are signed per the DCO using --signoff

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 42.85714% with 8 lines in your changes missing coverage. Please review.

Project coverage is 64.32%. Comparing base (3c5a506) to head (ea96379).
Report is 4 commits behind head on 2.x.

Files with missing lines	Patch %	Lines
...ng/language_service/default_language_reference.tsx	27.27%	8 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              2.x    #7902      +/-   ##
==========================================
- Coverage   64.34%   64.32%   -0.02%     
==========================================
  Files        3658     3659       +1     
  Lines       80842    80854      +12     
  Branches    12880    12880              
==========================================
- Hits        52016    52011       -5     
- Misses      25635    25652      +17     
  Partials     3191     3191              

Flag	Coverage Δ
Linux_1	30.31% <14.28%> (-0.01%)	⬇️
Linux_2	56.04% <ø> (ø)
Linux_3	40.77% <42.85%> (+<0.01%)	⬆️
Linux_4	31.59% <14.28%> (-0.01%)	⬇️
Windows_1	?
Windows_2	55.99% <ø> (ø)
Windows_3	40.77% <42.85%> (+<0.01%)	⬆️
Windows_4	31.59% <14.28%> (-0.01%)	⬇️

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