Check actions versions (we have discrepancy)

[anenadic]

E.g. @checkout is sometimes v4 and sometimes v5. Check other actions too.

The discrepancy comes after fixing the actions versions in #494 and #511 (from the Workbench).

[bielsnohr]

I think we should kick this to the next milestone. My rationale is so we can close December2025-beta without further scope creep, and therefore we shouldn't be adding any further items to this milestone unless they are super urgent and high priority.

[matt-graham]

@douglowe and I discussed at maintainer meeting on 2026/03/24 -one solution would be to set up dependabot (or an alternative solution such as renovate) to automate raising PRs to keep workflow action versions up to date. We both felt this would be a reasonable solution for both dealing with initial issue and getting more visibility over time when action update, but we wanted to check if there was any concerns about setting up something like this?