a0766ac236
This commit fixes the layout of the Reference
page. Previously, the toctree level was "2",
which made the page hard to navigate.
This PR changes the level to "1".
In addition, the capitalization of page
titles is fixed.
This is a follow-up PR to the ones that
created and updated the Reference section.
It must be backported to branch-5.4.
Closes scylladb/scylladb#15830
(cherry picked from commit e223624e2e)