Getting started failing on `/next/` targets, generating links to 404

[adrianrudnik]

Working through the docs, every few pages almost all sub-links to other topics seem to break.

Several examples:

• https://docs.crowdsec.net/u/getting_started/post_installation/profiles linking to https://docs.crowdsec.net/docs/next/profiles/format#profile-directives
• https://docs.crowdsec.net/u/getting_started/post_installation/whitelists linking to https://docs.crowdsec.net/docs/next/whitelist/intro, https://docs.crowdsec.net/docs/next/whitelist/create_expr
• https://docs.crowdsec.net/u/getting_started/post_installation/acquisition_new linking to https://docs.crowdsec.net/docs/next/data_sources/file, https://docs.crowdsec.net/docs/next/data_sources/intro
• https://docs.crowdsec.net/u/getting_started/post_installation/acquisition linking to https://docs.crowdsec.net/docs/next/collections/intro, https://docs.crowdsec.net/docs/next/parsers/intro, https://docs.crowdsec.net/docs/next/scenarios/intro

Is this expected, a caching issue or a general issue?

[LaurenceJJones]

Working through the docs, every few pages almost all sub-links to other topics seem to break.

Several examples:

* https://docs.crowdsec.net/u/getting_started/post_installation/profiles linking to https://docs.crowdsec.net/docs/next/profiles/format#profile-directives

* https://docs.crowdsec.net/u/getting_started/post_installation/whitelists linking to https://docs.crowdsec.net/docs/next/whitelist/intro, https://docs.crowdsec.net/docs/next/whitelist/create_expr

* https://docs.crowdsec.net/u/getting_started/post_installation/acquisition_new linking to https://docs.crowdsec.net/docs/next/data_sources/file, https://docs.crowdsec.net/docs/next/data_sources/intro

* https://docs.crowdsec.net/u/getting_started/post_installation/acquisition linking to https://docs.crowdsec.net/docs/next/collections/intro, https://docs.crowdsec.net/docs/next/parsers/intro, https://docs.crowdsec.net/docs/next/scenarios/intro

Is this expected, a caching issue or a general issue?

It is an issue, since /u/ is unversioned linking to a versioned page eg: /docs/next/ the docusarus linter doesnt know that these are broken links and didnt let us know.

cause we moved a bunch of links around within #666