Support latest ClientFlags (#1953)

This adds the Redis 6.0+ flags from #1912

src/StackExchange.Redis/ClientInfo.cs

@@ -47,6 +47,9 @@ public sealed class ClientInfo
         /// S: the client is a normal replica server
         /// U: the client is connected via a Unix domain socket
         /// x: the client is in a MULTI/EXEC context
+        /// t: the client enabled keys tracking in order to perform client side caching
+        /// R: the client tracking target client is invalid
+        /// B: the client enabled broadcast tracking mode
         /// </summary>
         public string FlagsRaw { get; private set; }
 
@@ -173,6 +176,10 @@ internal static ClientInfo[] Parse(string input)
                                 AddFlag(ref flags, value, ClientFlags.UnixDomainSocket, 'U');
                                 AddFlag(ref flags, value, ClientFlags.Transaction, 'x');
 
+                                AddFlag(ref flags, value, ClientFlags.KeysTracking, 't');
+                                AddFlag(ref flags, value, ClientFlags.TrackingTargetInvalid, 'R');
+                                AddFlag(ref flags, value, ClientFlags.BroadcastTracking, 'B');
+
                                 client.Flags = flags;
                                 break;
                             case "id": client.Id = Format.ParseInt64(value); break;

src/StackExchange.Redis/Enums/ClientFlags.cs

@@ -85,5 +85,17 @@ public enum ClientFlags : long
         /// the client is connected via a Unix domain socket
         /// </summary>
         UnixDomainSocket = 2048,
+        /// <summary>
+        /// the client enabled keys tracking in order to perform client side caching
+        /// </summary>
+        KeysTracking = 4096,
+        /// <summary>
+        /// the client tracking target client is invalid
+        /// </summary>
+        TrackingTargetInvalid = 8192,
+        /// <summary>
+        /// the client enabled broadcast tracking mode
+        /// </summary>
+        BroadcastTracking = 16384,
     }
 }