[fixed]button can also trigger the click event when loading is true

[120216220]

IE9 does not support pointer-events

fixed button can also trigger the click event when loading is true in IE9

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[codecov]

Codecov Report

Merging #12466 into master will decrease coverage by 0.01%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master   #12466      +/-   ##
==========================================
- Coverage   92.27%   92.25%   -0.02%     
==========================================
  Files         210      210              
  Lines        5487     5490       +3     
  Branches     1546     1547       +1     
==========================================
+ Hits         5063     5065       +2     
- Misses        420      421       +1     
  Partials        4        4

Impacted Files	Coverage Δ
components/button/button.tsx	93.9% <66.66%> (-1.04%)	⬇️

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[zombieJ]

Thanks for contribution. Code merged.