Reduce flakiness of Check Links CI job

[mfisher87]

Description

GitHub's unauthenticated rate limits make it impractical to check GitHub links. Link checks are regularly failing for 429 responses from GH.

This reduces the value of this job, but it also speeds it up 🤷 It's still going to catch other broken links.

See: #1254 (comment)

At the time it errored on https://www.gnu.org/software/inetutils/manual/html_node/The-_002enetrc-file.html, and the link really was broken. But it's back up now. So I guess that's just another example of this job being flaky, for reasons out of our control 🤷

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"Ready for review" checklist

• Open PR as draft
• Please review our Pull Request Guide
• Mark "ready for review" after following instructions in the guide

Merge checklist

• PR title is descriptive
• PR body contains links to related and resolved issues (e.g. closes #1)
• If needed, CHANGELOG.md updated
• If needed, docs and/or README.md updated
• If needed, unit tests added
• All checks passing (comment pre-commit.ci autofix if pre-commit is failing)
• At least one approval

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📚 Documentation preview 📚: https://earthaccess--1257.org.readthedocs.build/en/1257/

[github-actions]

👈 Launch a binder notebook on this branch for commit 199c6aa

I will automatically update this comment whenever this PR is modified

[mfisher87]

Thanks for the review!