C# 9 Cleanup (#325)

- [X] Removes EventArgs - not needed
- [X] Merges sequential checks
- [X] Removes redundant type declarations

Projects/Server/Network/NetState/NetState.cs

@@ -42,7 +42,7 @@ namespace Server.Network
         private static int HuePickerCap = 512;
         private static int MenuCap = 512;
 
-        private static readonly ConcurrentQueue<NetState> m_Disposed = new ConcurrentQueue<NetState>();
+        private static readonly ConcurrentQueue<NetState> m_Disposed = new();
         private static NetworkState m_NetworkState = NetworkState.ResumeState;
 
         public static NetStateCreatedCallback CreatedCallback { get; set; }