Fix StreamWindowScaleThresholdMultiplier_HighValue_WindowScalesSlower (…

…dotnet#56373)

src/libraries/System.Net.Http/tests/FunctionalTests/SocketsHttpHandlerTest.Http2FlowControl.cs

@@ -148,7 +148,7 @@ static async Task RunTest()
             }
 
             RemoteInvokeOptions options = new RemoteInvokeOptions();
-            options.StartInfo.EnvironmentVariables["DOTNET_SYSTEM_NET_HTTP_SOCKETSHTTPHANDLER_FLOWCONTROL_STREAMWINDOWSCALETHRESHOLDMULTIPLIER"] = "1000"; // Extreme value
+            options.StartInfo.EnvironmentVariables["DOTNET_SYSTEM_NET_HTTP_SOCKETSHTTPHANDLER_FLOWCONTROL_STREAMWINDOWSCALETHRESHOLDMULTIPLIER"] = "10000"; // Extreme value
 
             RemoteExecutor.Invoke(RunTest, options).Dispose();
         }