Quick compiler error fix

LayerMask.GetMask apparently doesn't like being called in constructor/static readonly field initializer

Assets/BossRoom/Scripts/Client/ClientInputSender.cs

     [RequireComponent(typeof(NetworkCharacterState))]
     public class ClientInputSender : NetworkedBehaviour
     {
-        private static readonly int NPCLayerMask = LayerMask.GetMask("NPCs");
+        private int m_NPCLayerMask;
         private NetworkCharacterState m_NetworkCharacter;
 
         /// <summary>
 
         void Awake()
         {
+            m_NPCLayerMask = LayerMask.GetMask("NPCs");
             m_NetworkCharacter = GetComponent<NetworkCharacterState>();
         }
 
                     m_NetworkCharacter.ClientSendActionRequest(ref chase_data);
 
                     //TODO fixme: there needs to be a better way to check if target is a PC or an NPC
-                    bool isTargetingNPC = hit.transform.gameObject.layer == NPCLayerMask;
+                    bool isTargetingNPC = hit.transform.gameObject.layer == m_NPCLayerMask;
 
                     if (isTargetingNPC)
                     {