Add test files to eslint using specialized tsconfig

[cmdcolin]

This issue is a little obscure but recent changes to this package changed the eslint config to use @typescript-eslint, and the eslint parser needs a tsconfig. However, the tsconfig only refers to the src directory. This PR keeps the current setup of tsconfig.json to only include "src" but has a special tsconfig.lint.json that includes the "test" directory. This allows the eslint to run over the test directory, but only makes it so that the build process outputs the src directory. Is test is included in the tsconfig.json, then nested subdirectories are outputted in dist for both src and test

[cmdcolin]

This same pattern may be able to be added to other parser packages

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (b418271) 88.06% compared to head (ed773f2) 88.06%.

❗ Current head ed773f2 differs from pull request most recent head 39339e6. Consider uploading reports for the commit 39339e6 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #145   +/-   ##
=======================================
  Coverage   88.06%   88.06%           
=======================================
  Files           7        7           
  Lines         578      578           
  Branches      144      144           
=======================================
  Hits          509      509           
  Misses         69       69           

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