Fleet UI: Update hover and focus states for dropdowns and inputfields

[RachelElysia]

Issue

Part 3 for #26231

Description

• Aligns dropdowns with design system
• Aligns input fields with design system

Screenshots

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.
• Added/updated automated tests
• A detailed QA plan exists on the associated ticket (if it isn't there, work with the product group's QA engineer to add it)
• Manual QA for all new/changed functionality

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.88%. Comparing base (aa16261) to head (33fd2b1).
Report is 15 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #26506      +/-   ##
==========================================
+ Coverage   63.85%   63.88%   +0.02%     
==========================================
  Files        1661     1661              
  Lines      159221   159187      -34     
  Branches     4181     4109      -72     
==========================================
+ Hits       101671   101691      +20     
+ Misses      49613    49559      -54     
  Partials     7937     7937              

Flag	Coverage Δ
frontend	53.99% <100.00%> (+0.30%)	⬆️

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