Feat(Slider, Badge, Dropdown, Nav) a11y support

[youluna]

No description provided.

[codecov]

Codecov Report

Merging #166 into feat/a11y will increase coverage by <.01%.
The diff coverage is 94.11%.

@@              Coverage Diff              @@
##           feat/a11y     #166      +/-   ##
=============================================
+ Coverage      90.84%   90.85%   +<.01%     
=============================================
  Files            241      241              
  Lines          12042    12055      +13     
  Branches        3141     3146       +5     
=============================================
+ Hits           10940    10952      +12     
- Misses          1096     1097       +1     
  Partials           6        6

Impacted Files	Coverage Δ
src/slider/slick/inner-slider.jsx	82.35% <ø> (ø)	⬆️
src/dropdown/index.jsx	100% <100%> (ø)	⬆️
src/menu/view/selectable-item.jsx	100% <100%> (ø)	⬆️
src/slider/slick/arrow.jsx	96.87% <100%> (ø)	⬆️
src/slider/slider.jsx	78.94% <100%> (ø)	⬆️
src/menu/view/item.jsx	90% <80%> (-0.67%)	⬇️

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