fix(Core/Spells): Silent Fang proc should not work in … (#16907)

fix(Spell/SpellInfoCorrections): Silent Fang proc should not work in arena

src/server/game/Spells/SpellInfoCorrections.cpp

@@ -4516,6 +4516,12 @@ void SpellMgr::LoadSpellInfoCorrections()
         spellInfo->AttributesEx3 |= SPELL_ATTR3_DOT_STACKING_RULE;
     });
 
+     // Silence
+    ApplySpellFix({ 18278 }, [](SpellInfo* spellInfo)
+    {
+        spellInfo->AttributesEx4 |= SPELL_ATTR4_NOT_IN_ARENA_OR_RATED_BATTLEGROUND;
+    });
+
     // Absorb Life
     ApplySpellFix({ 34239 }, [](SpellInfo* spellInfo)
     {