fix(na): exclude URLs that frequently fail in CI link checking

[mrjones-plip]

Description

I took the past 8 or so runs of the link checker script and found URLs that occurred more than once:

grep -v localhost:1313 403\ https\ digitalmedic.txt|grep https|sort|uniq -c|grep -v '1 h'
	2 https://docs.getdbt.com/docs/core/installation
	2 https://github.com/medic/cht-android/blob/master/.github/workflows/publish.yml
	2 https://github.com/medic/cht-core/blob/master/scripts/deploy/README.md
	2 https://github.com/medic/cht-core/tree/master/scripts/deploy
	2 https://github.com/palladiumkenya/openmrs-module-afyastat
	5 https://github.com/signup
	4 https://pmc.ncbi.nlm.nih.gov/articles/PMC6903365/
	3 https://ruky.me/hacking-cht-user-interface-with-javascript-to-format-content/

The DBT one has already been fixed, so this PR adds the others to the exclude list!

License

The software is provided under AGPL-3.0. Contributions to this project are accepted under the same license.

[andrablaj]

🧇