Make decaying spell bonuses not depend on CaclBonuses being called some other way

This just sets a flag that will tell us we need to recalc bonuses every tick

Before these kind of depended on it being caused some other way

zone/mob.cpp

@@ -425,6 +425,7 @@ Mob::Mob(const char* in_name,
 
 	emoteid = 0;
 	endur_upkeep = false;
+	degenerating_effects = false;
 	PrimaryAggro = false;
 	AssistAggro = false;
 	npc_assist_cap = 0;