The 515 MegaPR early downport (#7783)

Co-authored-by: Selis <selis@xynolabs.com>
Co-authored-by: Selis <sirlionfur@hotmail.de>
Co-authored-by: Kashargul <144968721+Kashargul@users.noreply.github.com>
Co-authored-by: SatinIsle <thesatinisle@gmail.com>
Co-authored-by: Heroman <alesha3000@list.ru>
Co-authored-by: Casey <a.roaming.shadow@gmail.com>
Co-authored-by: Raeschen <rycoop29@gmail.com>

code/modules/events/carp_migration.dm

@@ -75,7 +75,7 @@
 // Spawn a single carp at given location.
 /datum/event/carp_migration/proc/spawn_one_carp(var/loc)
 	var/mob/living/simple_mob/animal/M = new /mob/living/simple_mob/animal/space/carp/event(loc)
-	GLOB.destroyed_event.register(M, src, PROC_REF(on_carp_destruction))
+	RegisterSignal(M, COMSIG_OBSERVER_DESTROYED, PROC_REF(on_carp_destruction))
 	spawned_carp.Add(M)
 	return M
 
@@ -89,7 +89,7 @@
 // If carp is bomphed, remove it from the list.
 /datum/event/carp_migration/proc/on_carp_destruction(var/mob/M)
 	spawned_carp -= M
-	GLOB.destroyed_event.unregister(M, src, PROC_REF(on_carp_destruction))
+	UnregisterSignal(M, COMSIG_OBSERVER_DESTROYED)
 
 /datum/event/carp_migration/end()
 	. = ..()