feat(batch2): verify memstore remainder features

dotnet/tests/ZB.MOM.NatsNet.Server.Tests/JetStream/StorageEngineTests.cs

@@ -33,7 +33,7 @@ public class StorageEngineTests
     private static JetStreamMemStore NewMemStore(StreamConfig cfg)
     {
         cfg.Storage = StorageType.MemoryStorage;
-        return new JetStreamMemStore(cfg);
+        return JetStreamMemStore.NewMemStore(cfg);
     }
 
     private static byte[] Bytes(string s) => Encoding.UTF8.GetBytes(s);