Add continuous integration unit testing through GH Actions

[jdebacker]

This PR added a GH Action to run unit tests on pushes.

I have a work in progress label because I can't get unit tests to run locally. I just rebuilt the toxbrain-dev environment and when I run pytest, I get:

(taxbrain-dev) jason.debacker@JDEBACKER taxbrain % pytest
Traceback (most recent call last):
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/bin/pytest", line 7, in <module>
    from py.test import console_main
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/py/_vendored_packages/apipkg/__init__.py", line 199, in __getattribute__
    return getattr(getmod(), name)
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/py/_vendored_packages/apipkg/__init__.py", line 183, in getmod
    x = importobj(modpath, None)
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/py/_vendored_packages/apipkg/__init__.py", line 72, in importobj
    module = __import__(modpath, None, None, ['__doc__'])
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/pytest/__init__.py", line 5, in <module>
    from _pytest.assertion import register_assert_rewrite
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/_pytest/assertion/__init__.py", line 9, in <module>
    from _pytest.assertion import rewrite
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/_pytest/assertion/rewrite.py", line 34, in <module>
    from _pytest.assertion import util
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/_pytest/assertion/util.py", line 13, in <module>
    import _pytest._code
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/_pytest/_code/__init__.py", line 2, in <module>
    from .code import Code
  File "/Users/jason.debacker/anaconda3/envs/taxbrain-dev/lib/python3.8/site-packages/_pytest/_code/code.py", line 942, in <module>
    @attr.s(eq=False)
TypeError: attrs() got an unexpected keyword argument 'eq'

Once I am able to confirm tests run locally, I'll remove the WIP label.

[jdebacker]

Also, this PR would replace PR #22. I think GH Actions is a better solution than Travis at this point.

[jdebacker]

Ok, solved error above which was due to a deprecated version of a package that was installed due to package conflicts. Removing the pdflatex dependency, which was never imported in any module, solved this.

All tests (including Compute Studio app tests) are passing locally for me. Looking into why failures on the GH Action.

[jdebacker]

Took a few tries to figure out how to properly install texlive properly on the virtual machine, but this PR now ready for your review @andersonfrailey.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@5238a59). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #160   +/-   ##
=========================================
  Coverage          ?   81.83%           
=========================================
  Files             ?       21           
  Lines             ?     1448           
  Branches          ?        0           
=========================================
  Hits              ?     1185           
  Misses            ?      263           
  Partials          ?        0           

Flag	Coverage Δ
unittests	81.83% <0.00%> (?)

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[jdebacker]

@hdoupe Thanks for suggestion - one line worked!

[hdoupe]

@hdoupe Thanks for suggestion - one line worked!

Awesome, thanks for stepping up and figuring out how to get this to work.

[jdebacker]

This PR addresses Issue #106

[andersonfrailey]

Thanks for working on this, @jdebacker! LGTM. Merging.