Update CollapsePanelProps -> onChange function

[davidctj]

parameter key should be either an array of string(general) or string(accordion mode), right?

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[codecov]

Codecov Report

Merging #7084 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #7084   +/-   ##
======================================
  Coverage    85.8%   85.8%           
======================================
  Files         231     231           
  Lines        4951    4951           
  Branches     1411    1411           
======================================
  Hits         4248    4248           
  Misses        703     703

Impacted Files	Coverage Δ
components/collapse/Collapse.tsx	92.85% <ø> (ø)	⬆️

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