Help: Move deprecated modules and variables to dedicated sections

These were missed in commit e0355c4ea9 (FindBoost: Add policy to remove
this module, 2024-05-03, v3.30.0-rc1~150^2) and commit 0aba13a2f3
(ctest: Add explicit options for TLS server verification, 2024-03-01,
v3.30.0-rc1~408^2~3).