Replace Deprecated Link Checker

[macanudo527]

The current link checker has been deprecated:

https://github.com/gaurav-nelson/github-action-markdown-link-check

I'm replacing it with Lychee, which appears to be a battle-tested alternative.

I also fixed some mypy errors that came up because of the new version.

I also removed Python 3.8/9 from support since they are EOL.

[macanudo527]

@eprbell
This should be pretty straightforward stuff. I just updated it to the latest versions of things. I tried to stick to standard practices.

[eprbell]

Why not leave the check on in branches as well?

[macanudo527]

Basically, it just cuts down on unnecessary runs. It still runs on PR, but it won't run every single time you push an update. Sometimes when you are in the middle of a PR not everything works, so if you push a commit that doesn't complete the PR you'll get unnecessary warnings.

I mean I don't think it is necessary for every single commit push, do you?

[jayr0d]

Does this stop it from running in your own branch before you open a PR? You certainly want a clean run in your branch before opening the PR.

[macanudo527]

It stops it from running every time you push a commit that isn't part of a PR. It's basically just meant to cut down on test runs/reduce minutes used. I don't think we are ever at risk of using all the minutes up on the free plan, but it helps to be efficient. You can also run into issues if you submit multiple commits within a short amount of time, because caching can get corrupted etc... Less runs is generally better if you can get away with it.

As for having a 'dirty' run when you submit a PR, deadlinks aren't mission-critical, just an annoyance that can easily be fixed.

[jayr0d]

Hmm, just noticed this. I added .markdown-link-check.json in #148 to retry on HTTP 429 to get automated checks to pass. If pull request 146 gets merged I can update my branch and my pull request.

EDIT: We have some other conflicts to resolve, Python version, URLs, type/cast. Python version and URLs is easy for me to clean up second. I don't know the best approach for the type/cast mypy was complaining about. I am indifferent.

[jayr0d]

Other than on push/pr discussion, looks good to me. I was updating things across the board and we will need another similar pr for DaLI once this gets through.

I am also confused as to when we should be updating .pre-commit-config.yaml