Atomic: change http->https, and do a lot of refactoring

[keflavich]

Bugfix for #2065

[pep8speaks]

Hello @keflavich! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2021-06-21 19:41:27 UTC

[codecov]

Codecov Report

Merging #2088 (3e049f5) into main (0de7f0e) will decrease coverage by 0.00%.
The diff coverage is 33.33%.

@@            Coverage Diff             @@
##             main    #2088      +/-   ##
==========================================
- Coverage   66.56%   66.56%   -0.01%     
==========================================
  Files         407      407              
  Lines       27647    27652       +5     
==========================================
+ Hits        18403    18406       +3     
- Misses       9244     9246       +2     

Impacted Files	Coverage Δ
astroquery/atomic/__init__.py	91.07% <ø> (ø)
astroquery/atomic/core.py	37.90% <33.33%> (+0.92%)	⬆️
astroquery/gaia/core.py	61.59% <0.00%> (ø)

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[bsipocz]

Overall it looks good. I have added a few minor comments.
Do add a changelog entry though.

[keflavich]

@bsipocz note that this was a redundant header - we might have to remove this in other PRs too

[bsipocz]

oh, do remove it in one PR only, the other may end up in a conflict otherwise.

[bsipocz]

(@keflavich - in the future, do use one of the "magic" words before the issue number in PR descriptions, that case they got linked and closed automatically)

https://docs.github.com/en/issues/tracking-your-work-with-issues/creating-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword