feat: add avatar group component

[ruibaby]

What type of PR is this?

/area ui
/kind feature
/milestone 2.17.x

What this PR does / why we need it:

添加 AvatarGroup 组件，用于堆叠多个 Avatar 组件。

Which issue(s) this PR fixes:

Fixes #6079

Does this PR introduce a user-facing change?

添加 AvatarGroup 组件，用于堆叠多个头像。

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 54.73%. Comparing base (5fdf6c0) to head (b75a778).
Report is 257 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #6128      +/-   ##
============================================
- Coverage     56.91%   54.73%   -2.19%     
- Complexity     3319     3427     +108     
============================================
  Files           587      629      +42     
  Lines         18968    21209    +2241     
  Branches       1401     1482      +81     
============================================
+ Hits          10795    11608     +813     
- Misses         7594     9011    +1417     
- Partials        579      590      +11     

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[JohnNiang]

/approve

[f2c-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: JohnNiang

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• ui/OWNERS [JohnNiang]

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