Use tags instead of branches for major versions to enable updates with Renovate Bot

I use Renovate Bot to deal with dependency updates, but it is unable to keep pnpm/action-setup up to date.

In the actions community there is a convention to use a mutable major tags, very similar to how it's done with e.g. Docker. This is how all the official actions behave through the use of https://github.com/actions/publish-action. Renovate Bot uses tags as data sources for GitHub Actions accordingly.

This is also documented as the recommended way in the official documentation: https://docs.github.com/en/actions/sharing-automations/creating-actions/about-custom-actions#using-tags-for-release-management

This repository uses branches instead of tags for these major versions, and as such it is not picked up by Renovate Bot.

Would it be possible to change to use tags instead?

Start by reviewing how this repository currently represents major versions and publishes releases, then compare that setup with GitHub's recommended tag-based release management and the linked publish-action convention. Done means major-version tags replace the corresponding branches and Renovate can detect pnpm/action-setup updates through those tags.