Fixes https://github.com/scylladb/scylladb/issues/13915
This commit fixes broken links to the Enterprise docs.
They are links to the enterprise branch, which is not
published. The links to the Enterprise docs should include
"stable" instead of the branch name.
This commit must be backported to branch-5.2, because
the broken links are present in the published 5.2 docs.
Closes #13917
(cherry picked from commit 6f4a68175b)