Add a skip ci feature to the CI workflow

[eslavich]

This replicates the Travis feature where [skip ci] or [ci skip] in the commit message causes tests to be skipped.

[codecov]

Codecov Report

Merging #5591 (e4166ac) into master (93b8d5d) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #5591   +/-   ##
=======================================
  Coverage   74.39%   74.39%           
=======================================
  Files         416      416           
  Lines       38088    38088           
  Branches     5637     5637           
=======================================
  Hits        28336    28336           
  Misses       9752     9752           

Flag	Coverage Δ		*Carryforward flag
nightly	75.93% <ø> (ø)		Carriedforward from 93b8d5d
unit	54.56% <ø> (ø)

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[pllim]

Duplicate functionality as #5577 but different approach.

[pllim]

p.s. Is the addition of a file named foo intentional?

[eslavich]

p.s. Is the addition of a file named foo intentional?

Yea, that was just the change I made to show the behavior when [skip ci] is present. I'll remove that commit if we end up deciding to merge this.

[eslavich]

I attempted to make this version a reusable action, but evidently we're not permitted to nest an action (like checkout) within another action. I think @pllim's javascript action is the way to go, though I'm in favor of setting an output and checking it with an if: so that we can avoid a red X failure when the CI is skipped.

[pllim]

Yeah, composite action isn't a thing yet though it is widely requested. You can wait, but I am not sure for how long.

I'm in favor of setting an output and checking it

Looks like there is an option to set output in https://github.com/actions/toolkit/tree/main/packages/core . But I have to think about this. Maybe I'll make it an option whether to fail or just set the output, but that also complicates the documentation and logic.

[pllim]

For now though, if you can endure a red X, my action already works, as illustrated in the other PR, in case you need it immediately.

[jdavies-st]

Yeah, I don't think we want to endure red Xs for skipped CI. For jwst, the check should pass if CI is skipped.

Same is true for allowed failures, though that's a separate issue.

The way all this worked on Travis CI was very useful and we'd like to see that identical functionality in Github actions as well.

I would very much be in favor of the best of both these PRs getting put together.

[pllim]

That makes sense. I am looking into it.

[pllim]

I updated #5577 with your requested feature. Took me a while to get the output syntax right, but it seems to work now.

[eslavich]

Ok thanks a lot! Closing this one.

[pllim]

Here is the issue about composite action actions/runner#646