fix(Button): remove redundant role attribute

[floppyvlaDISK]

Fixes #3262.

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[codecov-io]

Codecov Report

Merging #3272 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #3272      +/-   ##
==========================================
+ Coverage   99.92%   99.92%   +<.01%     
==========================================
  Files         169      169              
  Lines        2803     2807       +4     
==========================================
+ Hits         2801     2805       +4     
  Misses          2        2

Impacted Files	Coverage Δ
src/elements/Button/Button.js	100% <100%> (ø)	⬆️

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