fix(Scripts/TempleOfAhnQiraj): Fix Vem enrage (#18652)

Fix Vem enrage

Vem should enrage when it is the last bug alive
(Regression from last refactor)

src/server/scripts/Kalimdor/TempleOfAhnQiraj/boss_bug_trio.cpp

@@ -390,6 +390,14 @@ struct boss_vem : public boss_bug_trio
         {
             DoCastVictim(SPELL_KNOCKDOWN);
             context.Repeat();
+        })
+        .Schedule(1s, [this](TaskContext context)
+        {
+            if (instance->GetData(DATA_BUG_TRIO_DEATH) == 2 && !me->HasAura(SPELL_VENGEANCE)) // Vem is the only one left.
+            {
+                DoCastSelf(SPELL_VENGEANCE, true);
+            }
+            context.Repeat(1s);
         });
     }
 };