Configure code coverage

[slecleach]

This is tested on my fork. It uploaded the coverage to my fork's codecov page.
https://app.codecov.io/github/slecleach/judo/commit/047fc7bf144df542aca7a3c16d07559e1263b296

This is covering the judo folder correctly:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 44.58%. Comparing base (5ab57f0) to head (047fc7b).
Report is 20 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main      #53       +/-   ##
===========================================
- Coverage   83.76%   44.58%   -39.19%     
===========================================
  Files           2       34       +32     
  Lines         191     1994     +1803     
  Branches        0      188      +188     
===========================================
+ Hits          160      889      +729     
- Misses         31     1063     +1032     
- Partials        0       42       +42     

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[alberthli]

As per slack discussion with @pculbertson, there seems to be a way to exclude __init__.py files from the coverage report, which would reduce the amount of over-reported coverage in the report. We should revisit this and make sure the number appears accurately.