MassInstallAction: Install the Downgrade workflow on this repository

[Krastanov]

This pull request sets up the Downgrade workflow on this repository. cc: @Krastanov

[coveralls]

Pull Request Test Coverage Report for Build 17294577419

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 83.422%

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Totals
Change from base Build 6207128573:	0.0%
Covered Lines:	1716
Relevant Lines:	2057

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💛 - Coveralls

[Krastanov]

The value of having this in CI is to ensure you are not inadvertently depending on features available only in recent versions of your dependencies. It also helps against accidentally having your users resolve to an antiquated version of dependencies (that is not really checked in CI). For more info, check this discussion: https://discourse.julialang.org/t/psa-add-downgrade-ci-to-better-check-version-compatibility/110063 (I will add a newer version of this action that solves some resolver issues, available since Julia con and already used in the SciML ecosystem)

It has already detected broken lower compat bounds in other repos in JuliaGraphs

In this particular case it seems the lower bounds present here are not consistent. I am not quite sure, I have not had this particular error before. Importantly, it probably hides more broken lower bounds.

Given that this package has active maintainers, I will not further pursue debugging and fixing this, but I would be happy to help if there are questions. The process to fix this would be to start bumping up the most outdated compat bounds. Moving the julia lower bounds to LTS will also be helpful.

Edit: my bad, it does not seem there are currently active maintainers. This PR needs more work, so marking as draft, for a time in the future when more folks are interested in reviving the package.