Run LinkChecker only once per week

[eshon]

Constant linkChecker issues from CI runs triggered by Docs PRs are problematic.

• No PR should be merged if a CI run fails.
• linkchecker issues sometimes prevent updates to the live Filecoin Docs site causing confusion among Contributors.
• ecosystem project links get updated, come and go, and sometimes take a while to load
• The linkChecker Github Action is here

Options:

Option 1. Run linkchecker via Github Actions only once per week if a PR is made that week

• This would require a dev like @lanzafame or Fil-B DevRel (@trruckerfling) to modify the Github Actions yml for this repo using something like https://github.com/orgs/community/discussions/26519

Option 2. People who know how to skip actions use that in their PRs and everyone else needs to held accountable for fixing broken linkchecker CI issues before merging PRs.

cc: @smagdali @robertagora @longfeiWan9 @xBalbinus

[BigLep]

Per DM, it looks like I was a contributor here with #2323 when I moved certain URLs out of <code> blocks. I'm game to engage here to improve the situation.

My thoughts:

1. Lets go with option 2 where we actually have branch protection rules that prevent pushing to the repo if the checks are failing. That way bad links don't build up. This way we have a mechanism rather than relying on best intentions.
2. Lets document the way to work around the link checking if someone needs to.
3. Lets get all links valid again.
4. (bonus) Lets add a badge for our link status.

I'll take a stab on this and update where I get to.

[BigLep]

I think this can be resolved once #2327 is closed.