fix(comp:modal): reading contains after onmounted causes an exception

[danranVm]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines
• Tests for the changes have been added/updated or not needed
• Docs and demo have been added/updated or not needed

What is the current behavior?

• 动画还未结束前就销毁了组件（例如：路由发生改变），会产生报错。
  

What is the new behavior?

Other information

[idux-bot]

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[codecov]

Codecov Report

Merging #1371 (48be1a0) into main (f19efbe) will not change coverage.
The diff coverage is 26.66%.

@@           Coverage Diff           @@
##             main    #1371   +/-   ##
=======================================
  Coverage   92.89%   92.89%           
=======================================
  Files         324      324           
  Lines       29850    29850           
  Branches     2474     2474           
=======================================
  Hits        27730    27730           
  Misses       2120     2120           

Impacted Files	Coverage Δ
packages/components/drawer/src/DrawerWrapper.tsx	83.12% <25.00%> (ø)
packages/components/modal/src/ModalWrapper.tsx	79.15% <28.57%> (ø)

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