fix(comp:cascader): when children changed,the scrollbar should be pinned

[danranVm]

fix #1316

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[idux-bot]

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[codecov]

Codecov Report

Merging #1353 (6f6a4b0) into main (f448714) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1353      +/-   ##
==========================================
- Coverage   93.10%   93.10%   -0.01%     
==========================================
  Files         323      323              
  Lines       29920    29917       -3     
  Branches     3397     3397              
==========================================
- Hits        27856    27853       -3     
  Misses       2064     2064              

Impacted Files	Coverage Δ
packages/components/empty/src/types.ts	100.00% <0.00%> (ø)

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