Switch CI to github actions

[lwasser]

currently we are building on travis CI but we need to move away from them given credits cost $$ and we run out given the size of our org.

I have things setup in abc-classroom however that is using a pip install and we really should be running conda forge.

TODOs:

• setup actions to run on conda / miniforge
• use the same action on abc-classroom to release to pypi --

[lwasser]

Update - this is working n ow and i'm building out the envt but what is odd is i think it's all still running on python 3.9
geopandas seems to use a matrix of envt files that specify the python version. that's a lot of work to maintain these.

[lwasser]

@nkorinek i left a note in asana but you could copy the actions for code cov and pypi over here in this PR (#631) if you want or it could be a separate pr!