CSS identificators needed in settings page when adding activity

[cdipe]

Since adding the Breakout Rooms option in the settings - which is great! - the settings section with CCS id="id_general" has been split over the page, and the identificator is used for several settings sections: Schedule, Security, Media and Host.
The new settings section "Breakout rooms" had it's own CSS id, id_breakoutrooms.
This messes everything up when using "guide systems", or Moodle internal guide/walktrough system, needing specific CSS identificators to point at each settings section.