Use GitHub Actions

[pllim]

Fix #499 .

Proof of concept as follows:

• Example log from CI workflow (push event): https://github.com/kali-maa/package-template/actions/runs/483659045
• Example log from deploy workflow (push event): https://github.com/kali-maa/package-template/actions/runs/483662995
• Example diff that should happen when this Action next runs here: https://github.com/kali-maa/package-template/commit/a62c2704ed3bd282c8b294590016a487f5bcc962

Some notes:

• I separated out CI and deploy based on recommendation from GitHub security lab.
• render job is not in a matrix because if inside a step isn't respected in a matrixed workflow, and you don't want to upload the artifact unnecessarily.
• Turns out checkout action is pretty nice as you don't need special SSH key by using it. But you do need a special token that allows "update github action workflows" and I already set that up for you. Would be nice if we can replace it with some org level token but I don't have access to that (some site says that is not even possible, so I am not sure).

Note to self:

• [x] Send out follow up memo in https://groups.google.com/g/astropy-dev/c/45frnTEAX-U/m/xwiQC2cuBAAJ after this is merged to announce the "completion" status of migration, with remaining stragglers to be handled as needed.

[pllim]

I added @bsipocz as a reviewer since she expressed interest to review. FYI and thanks!

[bsipocz]

Here is e.g. what I mean: when the parent is sunpy, I think this test header, and possibly other stuff as well, don't seem to be right. I recall this came up already in the header, or test runner, or somewhere (e.g. astropy should not be listed in the top, but rather as a dependency below, along with dependencies declared for "packagename", rather than a hard wired list). Also, I don't see any indications that the extra context is being tested, so with this matrix we only test that it doesn't error out?:

============================= test session starts ==============================
platform linux -- Python 3.8.6, pytest-6.2.1, py-1.10.0, pluggy-0.13.1
cachedir: .tox/py38-test/.pytest_cache

Running tests with Astropy version 4.2.
Running tests in packagename docs.

Date: 2021-01-13T19:45:18

Platform: Linux-5.4.0-1032-azure-x86_64-with-glibc2.2.5

Executable: /home/runner/work/package-template/test/packagename/.tox/py38-test/bin/python

Full Python Version: 
3.8.6 (default, Oct 28 2020, 13:08:18) 
[GCC 7.5.0]

encodings: sys: utf-8, locale: UTF-8, filesystem: utf-8
byteorder: little
float info: dig: 15, mant_dig: 15

Package versions: 
Numpy: 1.19.5
Scipy: not available
Matplotlib: not available
h5py: not available
Pandas: not available

Using Astropy options: remote_data: none.

rootdir: /home/runner/work/package-template/test/packagename, configfile: setup.cfg
plugins: hypothesis-6.0.1, arraydiff-0.3, doctestplus-0.8.0, astropy-header-0.1.2, remotedata-0.3.2, cov-2.10.1, filter-subpackage-0.1.1, openfiles-0.5.0
collected 3 items

[pllim]

test header

Yes, that is a separate issue already explained at https://github.com/astropy/pytest-astropy-header/issues/15#issuecomment-763247031 .

indications that the extra context is being tested

I am not sure what you mean. Compared to https://travis-ci.com/github/astropy/package-template/jobs/430750636 (where the parent is sunpy also), there are only 3 tests. For Actions, I run the codestyle and build_docs first and you can see the results if you expand the relevant steps before the tests.

[bsipocz]

@pllim - This PR is certainly replaces everything that we did with travis, and more. All I'm saying is that I don't see whether the extra contexts are being tested at all, beyond checking that no errors are raised using them. Probably I should have just opened a separate issue for it, as it clearly goes beyond this PR.

[pllim]

Yes, the matrix itself definitely can be improved for future PR. Shall we merge then? 😸

[bsipocz]

Oh, sure, I didn't mean that to be a blocker here more just as something I noticed, as this PR already improves the current status.