Update the style for the robot acccount ui

[AllForNothing]

1. Fixes The placeholder of quota search input is partly covered #19614
2. Fixes Robot account UI fields overlap #19617

Thank you for contributing to Harbor!

Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

Please indicate you've done the following:

• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

Merging #19663 (bf0cb65) into main (1cbc901) will increase coverage by 0.01%.
The diff coverage is 30.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #19663      +/-   ##
==========================================
+ Coverage   45.31%   45.33%   +0.01%     
==========================================
  Files         244      244              
  Lines       13331    13332       +1     
  Branches     2719     2719              
==========================================
+ Hits         6041     6044       +3     
+ Misses       6988     6986       -2     
  Partials      302      302              

Flag	Coverage Δ
unittests	45.33% <30.00%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...issions-panel/robot-permissions-panel.component.ts	55.93% <30.00%> (-7.87%)	⬇️

... and 2 files with indirect coverage changes

[wy65701436]

lgtm