chore: remove 'patch-package' and its unused frontend-build patch

[bradenmacdonald]

This reverts #1350 which added a patch to frontend-build to support a JS_CONFIG_FILEPATH env variable. I don't think it's used, but if 2U is still using this functionality, it's overdue to be merged into frontend-build instead of maintained on this patch.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.72%. Comparing base (0ac127e) to head (44a8397).
Report is 24 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1621   +/-   ##
=======================================
  Coverage   84.72%   84.72%           
=======================================
  Files         333      333           
  Lines        5709     5709           
  Branches     1368     1368           
=======================================
  Hits         4837     4837           
  Misses        855      855           
  Partials       17       17           

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[arbrandes]

Thanks, approved!

Let's wait a couple of days for somebody at 2U to give their ok before merging, though.

[bradenmacdonald]

@jansenk @jristau1984 We never heard back from you on this PR - could you please take a look and confirm it won't negatively affect 2U if we merge? Thanks! Slack thread