perf(SocketLayer): adding IEquatable to struct

removes allocations from ring buffer comparer

Assets/Mirage/Runtime/SocketLayer/AckSystem.cs

@@ -718,7 +718,7 @@ public override int GetHashCode()
                 return order;
             }
         }
-        public struct ReliableReceived
+        public struct ReliableReceived : IEquatable<ReliableReceived>
         {
             public readonly ByteBuffer buffer;
             public readonly int length;
@@ -735,6 +735,11 @@ public ReliableReceived(ByteBuffer buffer, int length, bool isFragment)
                 this.length = length;
                 this.isFragment = isFragment;
             }
+
+            public bool Equals(ReliableReceived other)
+            {
+                return buffer == other.buffer;
+            }
         }
     }
 }