Should fix pumpkins, PUMPKINS EVERYWHERE (#4881)

# About the pull request

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Commit from
cmss13-devs/cmss13-pve@0aa95b1

Turns out i'm a monkey and didn't think about This One Small Thing when
refactoring, so the decorator keeps applying even without being active.
Neat huh.

# Explain why it's good for the game
Pumpkins overstepping their bounds. It's not much of a holiday if it's
on all the time...


# Changelog
:cl: MorrowWolf
fix: Fixed Pumpkins appearing past season.
/:cl:

Co-authored-by: Morrow <[email protected]>

code/controllers/subsystem/game_decorator.dm

@@ -20,7 +20,7 @@ SUBSYSTEM_DEF(game_decorator)
 	var/defer_decoration = TRUE //! So map decoration is done post-setup after nightmare and spawners
 
 /datum/game_decorator/New()
-	if(defer_decoration)
+	if(defer_decoration && is_active_decor())
 		RegisterSignal(SSdcs, COMSIG_GLOB_MODE_POSTSETUP, PROC_REF(defered_decoration))
 
 /datum/game_decorator/proc/is_active_decor()