Fix dropping non-dimensional coordinates in grid_to_table

[Souza-junior]

Add lines to search for extra coordinates and append the information into the list of coordinates and coordinates_name

Fixes #403

Relevant issues/PRs:

[welcome]

💖 Thank you for opening your first pull request in this repository! 💖

A few things to keep in mind:

• Authorship Guidelines: Our rules for giving you credit for your contributions, including authorship on publications and Zenodo archives.
• Code of Conduct: How we expect people to interact in our projects.

⭐ No matter what, we are really grateful that you put in the effort to do this! ⭐

[leouieda]

Thanks for doing this @Souza-junior! Code looks good and the failed "style" check is not related to this (probably something updated in flake8) so you can ignore it.

All this needs now is a test. You can add one as a "doctest" here https://github.com/fatiando/verde/pull/441/files#diff-948da2a0e34f8cfb6c9d6b6498ec131890d1e637c8128eed5629fb5ce854dd7bR622

What I'd suggest is making a DataArray with extra coordinates and seeing if they are picked up properly.

[Souza-junior]

Hi @leouieda! I've added the test you asked for.

[leouieda]

Great! Thanks @Souza-junior 👍🏾

[welcome]

🎉 Congrats on merging your first pull request and welcome to the team! 🎉

If you would like to be added as a author on the Zenodo archive of the next release, add your full name, affiliation, and ORCID (optional) to the AUTHORS.md file of this repository. Feel free to do this in a new pull request if needed.

We hope that this was a good experience for you. Let us know if there is any way that the contributing process could be improved.

[leouieda]

Merged! Thanks @Souza-junior 🎉 Please add yourself to the AUTHORS.md file in a new PR.