Add GitHub Actions for eunit

[mpope9]

Include ASan defined here: https://github.com/mpope9/exor_filter/issues/17

[mpope9]

Good place to get started: https://github.com/marketplace/actions/setup-erlang

[mpope9]

Use OTP 23+

[JayKickliter]

This github workflow file is a complete example. The major difference is that I build that NIF with CMake, and the CMake script if there is an environment variable named SANITIZE_ERLANG_NIFS set and equal to 1. You could do the same thing this NIF's Makefile.

[mpope9]

Neat, thank you. Does coverage also hit the nif code? I don't know the difference between rebar3 cover and covertool

[JayKickliter]

The codecov only tracks erlang coverage. IIRC, that is using covertool.