Fleet UI: Hide redundant built in label filtering

[RachelElysia]

Issue

Cerra #21343

Description

• Hides redundant built in label filtering if the built in label is a part of the dropdown
• Clean up long label names awkwardly truncating much less wider than the dropdown space provided for the name

NOTE: We can't remove it for all labels as there's no other UI to get to edit/delete a custom label nor unclick a built in label that is not supported by the dropdown

Screenrecording

https://www.loom.com/share/5ec6b869f81140f1baed4186871e1bc6?sid=e79788df-9cdb-4e39-85ef-8734ae3f8e3f

Checklist for submitter

If some of the following don't apply, delete the relevant line.

• Changes file added for user-visible changes in changes/, orbit/changes/ or ee/fleetd-chrome/changes.
• Manual QA for all new/changed functionality

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 65.22%. Comparing base (b14f7fa) to head (911dc1c).
Report is 23 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #22308   +/-   ##
=======================================
  Coverage   65.22%   65.22%           
=======================================
  Files        1496     1496           
  Lines      117247   117247           
  Branches     3563     3566    +3     
=======================================
  Hits        76474    76474           
  Misses      33636    33636           
  Partials     7137     7137           

Flag	Coverage Δ
frontend	52.35% <ø> (ø)

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