Redirect old docs links to new Antora docs links

[pderop]

Documentation Issue

Once reactor-core documentation is migrated to Antora, some links to the documentations will change.
now, since we have some links to the current doc outside in the wild, like in https://www.canva.dev/blog/engineering/enabling-real-time-collaboration-with-rsocket/, where there is a link to https://projectreactor.io/docs/core/release/reference/#faq.mdc which is now https://projectreactor.io/docs/core/release/reference/faq.html#faq.mdc.

we need to redirect old links to new ones.

Improvement Suggestion

for some cases, it might be possible to use Antora page-aliases attributes.
For other cases, we might need to configure some redirect mapping in Cloudflare.

Additional context