install-cylc-components: respect login shell

[oliver-sanders]

Use a Bash login shell.

This opens up working with Micromamba managed environments.

Checklist

• I have read the contributing instructions in README.md and have opened this against the correct branch & milestone

[MetRonnie]

I think we should use bash -elo pipefail {0}? https://docs.github.com/en/actions/writing-workflows/workflow-syntax-for-github-actions#defaultsrunshell

[oliver-sanders]

Will give this a try with the downstream PRs.

Test: oliver-sanders/cylc-rose#5

[oliver-sanders]

Hmmm. The action is running fine, but errors are appearing downstream (which doesn't make sense).

Can see some set -u error coming from profile.d stuff (which we have no control over), will try without 🤷 .

That seems to have worked: https://github.com/oliver-sanders/cylc-rose/actions/runs/13674608714/job/38232630689?pr=5

[MetRonnie]

Actually would it be worth adding a test for this to?

release-actions/.github/workflows/test.yml

Lines 1 to 3 in 04781c7

	name: Test
	# Limited unit testing of the actions

[oliver-sanders]

@MetRonnie, added a simple test.

[MetRonnie]

Sorry, to clarify I meant testing with setup-micromamba, although testing with both in a matrix might be good.

[oliver-sanders]

Done.