Fix double click event for CheckBox(Button) and Radio(Button)

[yxngl]

Fix #940 for these label wrapped input. Clicking label will also trigger event on input. related to #711

[codecov]

Codecov Report

Merging #1290 into dev will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##              dev    #1290   +/-   ##
=======================================
  Coverage   45.89%   45.89%           
=======================================
  Files          41       41           
  Lines        1340     1340           
  Branches      416      416           
=======================================
  Hits          615      615           
  Misses        705      705           
  Partials       20       20

Impacted Files	Coverage Δ
src/components/checkbox/CheckboxButton.vue	87.5% <ø> (ø)	⬆️
src/components/radio/RadioButton.vue	40% <ø> (ø)	⬆️
src/components/radio/Radio.vue	40% <ø> (ø)	⬆️
src/components/checkbox/Checkbox.vue	100% <ø> (ø)	⬆️

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[jtommy]

Thanks

[yxngl]

This together with the PR on Switch give only one click event, but the event target could be form different elements which depends on the interaction and usually not the input element, such as span.control-label or span.check