remove duplicate initialize

src/csharp/Grpc.Core.Tests/ClientServerTest.cs

@@ -82,8 +82,6 @@ namespace Grpc.Core.Tests
         [SetUp]
         public void Init()
         {
-            GrpcEnvironment.Initialize();
-
             server = new Server();
             server.AddServiceDefinition(ServiceDefinition);
             int port = server.AddListeningPort(Host + ":0");