Scripts/Magisters Terrace: Removed not allowed ENSURE_AI call from constructor

Closes #20727

src/server/scripts/EasternKingdoms/MagistersTerrace/boss_priestess_delrissa.cpp

@@ -360,7 +360,6 @@ struct boss_priestess_lackey_commonAI : public ScriptedAI
     {
         Initialize();
         instance = creature->GetInstanceScript();
-        AcquireGUIDs();
     }
 
     void Initialize()
@@ -384,6 +383,7 @@ struct boss_priestess_lackey_commonAI : public ScriptedAI
     void Reset() override
     {
         Initialize();
+        AcquireGUIDs();
 
         // in case she is not alive and Reset was for some reason called, respawn her (most likely party wipe after killing her)
         if (Creature* pDelrissa = ObjectAccessor::GetCreature(*me, instance->GetGuidData(DATA_DELRISSA)))