Quarantine template test (#19976)

src/ProjectTemplates/test/ItemTemplateTests/BlazorServerTests.cs

@@ -2,6 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Testing;
 using Templates.Test.Helpers;
 using Xunit;
 using Xunit.Abstractions;
@@ -22,6 +23,7 @@ namespace Templates.Items.Test
         public ITestOutputHelper Output { get; }
 
         [Fact]
+        [QuarantinedTest]
         public async Task BlazorServerItemTemplate()
         {
             Project = await ProjectFactory.GetOrCreateProject("razorcomponentitem", Output);