[BD-46] fix: fixed ModalDialog.Header sizes

[PKulkoRaccoonGang]

Description

Issue: #2850

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MadalDialog component

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (90a19e0) 92.89% compared to head (5cf6ceb) 92.83%.
Report is 9 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2925      +/-   ##
==========================================
- Coverage   92.89%   92.83%   -0.07%     
==========================================
  Files         235      235              
  Lines        4338     4245      -93     
  Branches     1056     1032      -24     
==========================================
- Hits         4030     3941      -89     
+ Misses        304      300       -4     
  Partials        4        4              

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[openedx-semantic-release-bot]

🎉 This PR is included in version 21.11.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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[openedx-semantic-release-bot]

🎉 This PR is included in version 22.0.0-alpha.23 🎉

The release is available on:

• npm package (@alpha dist-tag)
• GitHub release

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