Fix all of the nullable issues

MistoxServer/mPacket/DataPacket.cs

@@ -46,10 +46,10 @@ namespace Mistox {
             return writer.WrittenSpan.ToArray();
         }
 
-        public static object Deserialize( DataPacketHeader Header, ReadOnlyMemory<byte> Data ) {
+        public static object? Deserialize( DataPacketHeader Header, ReadOnlyMemory<byte> Data ) {
             
             // Get the type from the tag
-            if (!NetworkPacketDictionary.PacketLookupTable.TryGetValue(Header.Type, out Type resolvedType)) {
+            if (!NetworkPacketDictionary.PacketLookupTable.TryGetValue(Header.Type, out Type? resolvedType)) {
                 throw new Exception($"Unknown packet type ID: {Header.Type}");
             }