test(ui): add Avatar test case

[summericy]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our Commit Message Guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[github-actions]

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[codecov]

Codecov Report

Merging #286 (ef43d29) into main (22034a6) will increase coverage by 100.00%.
Report is 476 commits behind head on main.
The diff coverage is n/a.

Additional details and impacted files

@@             Coverage Diff             @@
##           main      #286        +/-   ##
===========================================
+ Coverage      0   100.00%   +100.00%     
===========================================
  Files         0         4         +4     
  Lines         0        97        +97     
  Branches      0        39        +39     
===========================================
+ Hits          0        97        +97     

see 4 files with indirect coverage changes