Test Geojson file fields

[Antsalacia]

Add test in earthspy.py to test the field name and the coordinates

[AdrienWehrle]

Thanks for working on this @Antsalacia! :)
Can you try and revert earthspy.py to its main version? So that only the changes to test_earthspy.py appear here. You can check how to do it here: https://stackoverflow.com/questions/1817766/how-to-revert-to-origins-master-branchs-version-of-file

[AdrienWehrle]

Next we'd need a test checking that the last coordinate is the same as the first one (as this is needed for a polygon).

[AdrienWehrle]

I just resolved the conflicts, we're almost good to go! :)

[AdrienWehrle]

There's still a couple of pre-commit issues to fix, but most of them will be fixed if you push the code once it has been formatted by black, that is, right after you ran pre-commit.

[AdrienWehrle]

closes #34