Quarantine flaky BlazorWebJsInitializersTest.InitializersRunsModernCallbacksByDefaultWhenPresent (#68857)

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src/Components/test/E2ETest/ServerRenderingTests/BlazorWebJsInitializersTest.cs

@@ -29,6 +29,7 @@ public override Task InitializeAsync()
 
     [Theory]
     [MemberData(nameof(InitializerTestData))]
+    [QuarantinedTest("https://github.com/dotnet/aspnetcore/issues/68856")]
     public void InitializersRunsModernCallbacksByDefaultWhenPresent(bool streaming, bool webassembly, bool server, string[] expectedInvokedCallbacks)
     {
         var url = $"{ServerPathBase}/initializers?streaming={streaming}&wasm={webassembly}&server={server}";