Add lockfile-lint to check for bad errors in yarn.lock

[julienw]

The article [1] describes possible attacks that can be conveyed using
yarn.lock. This tool lockfile-lint helps avoid common threats.

[1] https://snyk.io/blog/why-npm-lockfiles-can-be-a-security-blindspot-for-injecting-malicious-modules/

[codecov]

Codecov Report

Merging #2278 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2278   +/-   ##
=======================================
  Coverage   86.11%   86.11%           
=======================================
  Files         203      203           
  Lines       14824    14824           
  Branches     3713     3713           
=======================================
  Hits        12766    12766           
  Misses       1886     1886           
  Partials      172      172

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[gregtatum]

Works for me, thanks for ensuring we are more secure.