style: changed display of anticon

[x1mrdonut1x]

🤔 This is a ...

• New feature
• Bug fix
• Site / document update
• Component style update
• TypeScript definition update
• Refactoring
• Code style optimization
• Test Case
• Branch merge
• Other (about what?)

💡 Background and solution

I found the icon transition when collapsing the Menu component to not look very nice.

Old solution:

broken icon transition

New solution:

Seamless icon transition

☑️ Self Check before Merge

⚠️ Please check all items below before review. ⚠️

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• TypeScript definition is updated/provided or not needed
• Changelog is provided or not needed

[ant-design-bot]

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit 597f460:

Sandbox	Source
antd reproduction template	Configuration

[codecov]

Codecov Report

Merging #22090 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #22090   +/-   ##
=======================================
  Coverage   97.96%   97.96%           
=======================================
  Files         306      306           
  Lines        7041     7041           
  Branches     1928     1939   +11     
=======================================
  Hits         6898     6898           
  Misses        143      143

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