remove readonly of AuthenticationConnection in Session

Author: wizicer

src/Renci.SshNet/Session.cs

@@ -85,7 +85,7 @@ public class Session : ISession
         /// <remarks>
         /// Some server may restrict number to prevent authentication attacks
         /// </remarks>
-        private static readonly SemaphoreLight AuthenticationConnection = new SemaphoreLight(3);
+        private static SemaphoreLight AuthenticationConnection = new SemaphoreLight(3);
 
         /// <summary>
         /// Holds metada about session messages
@@ -948,7 +948,7 @@ internal void SendMessage(Message message)
                 // increment the packet sequence number only after we're sure the packet has
                 // been sent; even though it's only used for the MAC, it needs to be incremented
                 // for each package sent.
-                // 
+                //
                 // the server will use it to verify the data integrity, and as such the order in
                 // which messages are sent must follow the outbound packet sequence number
                 _outboundPacketSequence++;
@@ -1074,12 +1074,12 @@ private Message ReceiveMessage(Socket socket)
 
                 // Construct buffer for holding the payload and the inbound packet sequence as we need both in order
                 // to generate the hash.
-                // 
+                //
                 // The total length of the "data" buffer is an addition of:
                 // - inboundPacketSequenceLength (4 bytes)
                 // - packetLength
                 // - serverMacLength
-                // 
+                //
                 // We include the inbound packet sequence to allow us to have the the full SSH packet in a single
                 // byte[] for the purpose of calculating the client hash. Room for the server MAC is foreseen
                 // to read the packet including server MAC in a single pass (except for the initial block).
@@ -1842,7 +1842,7 @@ private void MessageListener()
                         //   => the socket will be removed from "readSockets"
                         // * the socket is disposed during the Select invocation
                         //   => the socket will not be removed from "readSocket"
-                        // 
+                        //
                         // since we handle the second and third condition the same way and Socket.Connected
                         // allows us to check for both conditions, we use that instead of both checking for
                         // the removal from "readSockets" and the Connection check