Convert some bools to TRUE/FALSE instead of 1/0. (#11100)

Co-authored-by: Aronai Sieyes <arokha@arokha.com>

code/game/objects/structures/displaycase.dm

@@ -3,9 +3,9 @@
 	icon = 'icons/obj/stationobjs.dmi'
 	icon_state = "glassbox1"
 	desc = "A display case for prized possessions. It taunts you to kick it."
-	density = 1
-	anchored = 1
-	unacidable = 1//Dissolving the case would also delete the gun.
+	density = TRUE
+	anchored = TRUE
+	unacidable = TRUE//Dissolving the case would also delete the gun.
 	var/health = 30
 	var/occupied = 1
 	var/destroyed = 0