Core/Spells: Force spell 51590 (Toss Ice Boulder) to only affect one

target.

src/server/game/Spells/SpellMgr.cpp

@@ -4102,6 +4102,10 @@ void SpellMgr::LoadSpellCustomAttr()
             spellInfo->Effect[1] = 0;
             count++;
             break;
+        case 51590: // Toss Ice Boulder
+            spellInfo->MaxAffectedTargets = 1;
+            count++;
+            break;
         default:
             break;
         }