Update documentation for private vulnerability repository

[nscuro]

Description

This PR updates the documentation for DT's private vulnerability repository feature, as the current documentation is outdated.

It also downgrades jekyll to version 3.9.x again, as GitHub Pages does not yet support Jekyll 4.x yet, according to https://pages.github.com/versions/

Addressed Issue

Fixes #2703

Additional Details

N/A

Checklist

• I have read and understand the contributing guidelines
• This PR fixes a defect, and I have provided tests to verify that the fix is effective
• This PR implements an enhancement, and I have provided tests to verify that it works as intended
• This PR introduces changes to the database model, and I have added corresponding update logic
• This PR introduces new or alters existing behavior, and I have updated the documentation accordingly

[leec94]

The images aren't showing, they show up as links. and when clicking the links they result in a 404. Looks like it may be because the images are in a docs folder. If the docs are generated in a different way that might not be an issue. Otherwise, the changes look good, documentation is clear and the images are helpful.

[nscuro]

Thanks @leec94, appreciate the review! 🙌

The images aren't showing, they show up as links. and when clicking the links they result in a 404. Looks like it may be because the images are in a docs folder. If the docs are generated in a different way that might not be an issue.

Hmmm, did you build the docs? Sadly the markdown sources by themself are almost useless in sites built with Jekyll, mostly due to the linking issues you mentioned :(

[leec94]

i was able to run jekyll to view the generated docs, and i can see the images. both content and images look great!

[leec94]

after deleting Gemfile.lock, running ./dev/scripts/docs-dev-docker.sh works to generate the documentation as well.

[nscuro]

Thanks for the review @leec94!