fix(Radio): fix radio group preview

[byeval]

• checkbox group preview use label & children
• radio group preview use label & children

[codecov]

Codecov Report

Merging #1391 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1391      +/-   ##
==========================================
+ Coverage   90.04%   90.04%   +<.01%     
==========================================
  Files         270      270              
  Lines       15191    15205      +14     
  Branches     4922     4928       +6     
==========================================
+ Hits        13678    13692      +14     
  Misses       1487     1487              
  Partials       26       26

Impacted Files	Coverage Δ
src/radio/radio-group.jsx	97.1% <100%> (+0.32%)	⬆️
src/checkbox/checkbox-group.jsx	95.71% <100%> (+0.55%)	⬆️
src/tab/tabs/nav.jsx	91.66% <0%> (-0.04%)	⬇️

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