chore: Underline styles for popover text trigger

[georgylobko]

Description

AWSUI-59855
Replaced border bottom with underline dotted styles.

Related links, issue #, if available: n/a

How has this been tested?

Review checklist

The following items are to be evaluated by the author(s) and the reviewer(s).

Correctness

• Changes include appropriate documentation updates.
• Changes are backward-compatible if not indicated, see CONTRIBUTING.md.
• Changes do not include unsupported browser features, see CONTRIBUTING.md.
• Changes were manually tested for accessibility, see accessibility guidelines.

Security

• If the code handles URLs: all URLs are validated through the checkSafeUrl function.

Testing

• Changes are covered with new/existing unit tests?
• Changes are covered with new/existing integration tests?

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.41%. Comparing base (f9aeff8) to head (639d40f).

Additional details and impacted files

@@           Coverage Diff            @@
##             main    #3060    +/-   ##
========================================
  Coverage   96.41%   96.41%            
========================================
  Files         784      784            
  Lines       22168    22168            
  Branches     7206     7608   +402     
========================================
  Hits        21373    21373            
  Misses        788      788            
  Partials        7        7            

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[michaeldowseza]

Are all visual differences to be expected from this? e.g. Slight change in dotted line + slight shift in where the popover appears from?

[georgylobko]

@michaeldowseza
I’ve addressed this discrepancy and reviewed the screenshot tests in my dev pipeline. Everything looks good now.

[georgylobko]

I think we need a designer’s input to review the changes in this PR. @jkuelz
Posting all main diffs we have now:

live:

current (underline applies only to the text, not to the icon):

live:

current (the underline became thicker):

live:

current (multi-line underline, which is the whole point of this PR):