fix (module: select): Fix showing the arrow in SelectContent when mode is multiple

[agolub-s]

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• New feature
• Bug fix
• Site / documentation update
• Demo update
• Component style update
• Bundle size optimization
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🔗 Related issue link

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Fix showing the arrow in SelectContent when mode is multiple
🇨🇳 Chinese	修复了当模式为多个时在“选择内容”中显示箭头的问题

☑️ 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
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[github-actions]

[codecov]

Codecov Report

Patch coverage: 87.50% and project coverage change: +1.52% 🎉

Comparison is base (cd51775) 45.37% compared to head (2f5fd43) 46.89%.
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3430      +/-   ##
==========================================
+ Coverage   45.37%   46.89%   +1.52%     
==========================================
  Files         558      560       +2     
  Lines       26855    26845      -10     
  Branches      268      268              
==========================================
+ Hits        12185    12590     +405     
+ Misses      14630    14215     -415     
  Partials       40       40              

Files Changed	Coverage Δ
components/select/internal/SelectContent.razor	61.81% <ø> (+0.17%)	⬆️
components/select/internal/SelectSuffixIcon.razor	81.81% <81.81%> (ø)
...mponents/select/internal/SelectSuffixIcon.razor.cs	100.00% <100.00%> (ø)

... and 25 files with indirect coverage changes

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