Bump client version

src/Impostor.Server/Net/Manager/ClientManager.cs

@@ -22,7 +22,7 @@ namespace Impostor.Server.Net.Manager
         // NOTE: when updating this array, keep the versions ordered from old to new, otherwise the version compare logic doesn't work properly
         private static readonly int[] SupportedVersions =
         {
-            GameVersion.GetVersion(2021, 4, 25), // 2021.6.15
+            GameVersion.GetVersion(2021, 6, 30), // 2021.6.30
         };
 
         private readonly ILogger<ClientManager> _logger;