Icon smoothing for asteroid rocks (#8058)

Co-authored-by: Tomeno <tomeno@lulzsec.co.uk>

Content.Shared/Mining/AsteroidRockVisuals.cs

@@ -1,11 +0,0 @@
-using System;
-using Robust.Shared.Serialization;
-
-namespace Content.Shared.Mining
-{
-    [Serializable, NetSerializable]
-    public enum AsteroidRockVisuals
-    {
-        State
-    }
-}