Tests: fix SocketFailureError for Appveyor

StackExchange.Redis.Tests/ConnectionFailedErrors.cs

@@ -77,13 +77,16 @@ public void SocketFailureError()
             options.Ssl = true;
             options.Password = "";
             options.AbortOnConnectFail = false;
+            var ex = Assert.Throws<RedisConnectionException>(() =>
+            {
                 using (var muxer = ConnectionMultiplexer.Connect(options))
                 {
-                var ex = Assert.Throws<RedisConnectionException>(() => muxer.GetDatabase().Ping());
+                    muxer.GetDatabase().Ping();
+                }
+            });
             var rde = (RedisConnectionException)ex.InnerException;
             Assert.Equal(ConnectionFailureType.SocketFailure, rde.FailureType);
         }
-        }
 #if DEBUG // needs AllowConnect, which is DEBUG only
         [Fact]
         public void AbortOnConnectFailFalseConnectTimeoutError()