Fix and un-quarantine CanUseAntiforgeryAfterInitialRender test (#63640)

* Un-quarantine CanUseAntiforgeryAfterInitialRender test, try to fix its flakiness

* Add interactive rendering check to test component, simplify test assertion

Author: oroztocil

src/Components/test/E2ETest/ServerRenderingTests/FormHandlingTests/AntiforgeryTests.cs

@@ -33,7 +33,6 @@ public override Task InitializeAsync()
     [Theory]
     [InlineData("server")]
     [InlineData("webassembly")]
-    [QuarantinedTest("https://github.com/dotnet/aspnetcore/issues/57766")]
     public void CanUseAntiforgeryAfterInitialRender(string target)
     {
         Navigate($"{ServerPathBase}/{target}-antiforgery-form");
@@ -47,7 +46,6 @@ public void CanUseAntiforgeryAfterInitialRender(string target)
         var submit = Browser.Exists(By.Id("submit"));
         submit.Click();
 
-        var result = Browser.Exists(By.Id("result"));
-        Browser.Equal("Test", () => result.Text);
+        Browser.Equal("Test", () => Browser.FindElement(By.Id("result")).Text);
     }
 }

src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/Forms/ServerAntiforgeryForm.razor

@@ -6,7 +6,7 @@
 {
     <TestContentPackage.InteractiveAntiforgery RenderForm="bool.Parse(RenderForm)" />
 }
-else
+else if (RendererInfo.IsInteractive)
 {
     <p id="result">@Name</p>
 }