chore: Update padding for button dropdown with main action

[timogasda]

Description

The padding for the button dropdown with main action looked a little bit unbalanced. This change fixes that problem.

Related links, issue #, if available: AWSUI-22498

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 lines are covered by tests ✅

Comparison is base (7fa1db8) 94.19% compared to head (d2841f3) 94.19%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1673   +/-   ##
=======================================
  Coverage   94.19%   94.19%           
=======================================
  Files         650      650           
  Lines       17530    17530           
  Branches     5771     5771           
=======================================
  Hits        16513    16513           
  Misses        948      948           
  Partials       69       69           

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