This commit adds files that contain Open Source-specific information
and includes these files with the .. scylladb_include_flag:: directive.
The files include a) a link and b) Table of Contents.
The purpose of this update is to enable adding
Open Source/Enterprise-specific information in the Reference section.
(cherry picked from commit 680405b465)
Closesscylladb/scylladb#19395
5fe531fcb2