build: run ShellCheck in CI

[kdmccormick]

Description

build: run ShellCheck

Adds a ShellCheck check to edx-platform PRs and master,
using the shared workflow & template from the .github repo.
This will become a "required" check once it passes for 2 straight weeks on master.

Brings all existing shell scripts into compliance with ShellCheck.

Supporting information

This implements an ADR:

• docs: add ADR to adopt ShellCheck .github#60

and uses a new workflow template & action:

• build: provide ShellCheck shared workflow & template .github#64

This required removing some old, unused shell scripts which had a lot of violations:

• refactor!: remove unused update-assets-dev.sh #31810
• refactor!: remove unused provisioning scripts #31811
• refactor!: remove Jenkins CI scripts #31812

Other Information

See openedx/.github#64 for screenshots of the build.

Commits will be squashed before merging.

Test instructions

• Make a branch off of this one.
• Edit a shell script. Add something incorrect, like ls $whoops.
• Push the branch, and observe that the shellcheck PR check fails. (Unfortunately, due to GHA security restrictions, you may need to push an openedx/edx-platform upstream branch for this to work, which is only available to edx-platform CCs and 2U. After this PR merges, I expect that the check will also run on forks, which I will confirm).
• Look at the check output. Ensure that is easy to find and helpful.
• See if you can recreate the build failure on your local machine given the info in the output.

[brian-smith-tcril]

so it seems one of the reasons this is failing because https://github.com/openedx/edx-platform/blob/master/common/test/data/static/contains.sh is shebanging zsh, so we're getting this error:

./common/test/data/static/contains.sh:1:1: error: ShellCheck only supports sh/bash/dash/ksh scripts. Sorry! [SC1071]

is the lack of zsh support in shellcheck going to be a dealbreaker?

[kdmccormick]

That's a really old script, so I think we can just tell shellcheck ignore it. I don't think we should be committing zsh to repos for the same reason we wouldn't commit Ruby or Go: they're not Python, JS, or standard *nix tooling.

[feanil]

Just making a note that this needs to be updated before we merge this, I see that you have the comment ready to swap, when the .github PR has merged.

[kdmccormick]

Thanks for the reminder 👍🏻

[kdmccormick]

This and openedx/.github#64 are both ready for another round of review.

[feanil]

Looks good once the upstream .github PR merges and we do the final update to the job URL.

[edx-pipeline-bot]

EdX Release Notice: This PR has been deployed to the staging environment in preparation for a release to production.

[edx-pipeline-bot]

EdX Release Notice: This PR has been deployed to the production environment.

[edx-pipeline-bot]

EdX Release Notice: This PR has been deployed to the production environment.