Scripts/Icecrown Citadel: Removed unneccessary PreventDefaultAction call

Closes #1943

src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp

@@ -1034,7 +1034,6 @@ class spell_sindragosa_instability : public SpellScriptLoader
 
             void OnRemove(AuraEffect const* aurEff, AuraEffectHandleModes /*mode*/)
             {
-                PreventDefaultAction();
                 if (GetTargetApplication()->GetRemoveMode() == AURA_REMOVE_BY_EXPIRE)
                     GetTarget()->CastCustomSpell(SPELL_BACKLASH, SPELLVALUE_BASE_POINT0, aurEff->GetAmount(), GetTarget(), true, NULL, aurEff, GetCasterGUID());
             }