fix(switch): Update switch checked styling on foundation init

[rlfriedman]

This fixes an issue where Firefox would remember the state of the hidden input element on refresh which could result in a mismatch between switch styling and actual checked state.

[codecov-io]

Codecov Report

Merging #3147 into feat/switch-update will increase coverage by <.01%.
The diff coverage is 100%.

@@                  Coverage Diff                   @@
##           feat/switch-update    #3147      +/-   ##
======================================================
+ Coverage               98.32%   98.32%   +<.01%     
======================================================
  Files                     104      104              
  Lines                    4538     4540       +2     
  Branches                  587      587              
======================================================
+ Hits                     4462     4464       +2     
  Misses                     76       76

Impacted Files	Coverage Δ
packages/mdc-switch/foundation.js	100% <100%> (ø)	⬆️

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[kfranqueiro]

Tested on all browsers I could on OS X and Windows. In some I was able to test by navigating to a new page then going back, rather than refreshing. Looks like it's working everywhere.