Ignore link check failures for xmllint man page

[aj-stein-nist]

Committer Notes

Ignore linux.die.net man page mirror which seems to fail link update PR and other commits targeting develop and main. Closes #1926 for good (with a related but different failure).

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[aj-stein-nist]

It appears my merge of #1929 was probably best intended for the target branch of main, not develop. (The periodic GHA job actually targets main by default, I am not sure why that escaped my memory whilst reviewing and approving.)🤦 I am not sure the very best course of action is to cherry-pick that commit onto here and cause a potential conflict, or better is to revert off of develop, re-merge that same change onto main, add this, and then rebase develop off the updated main. TBD for tomorrow's standup.

[nikitawootten-nist]

Simple small fix. LGTM