Try a different approach, since I forgot our CI does use VS

Author: davidwengier

src/Razor/test/Microsoft.VisualStudio.Razor.IntegrationTests/VSOnlyIdeFactAttribute.cs src/Razor/test/Microsoft.VisualStudio.Razor.IntegrationTests/ManualRunOnlyIdeFactAttribute.cs

@@ -7,13 +7,13 @@
 namespace Microsoft.VisualStudio.Razor.IntegrationTests;
 
 [AttributeUsage(AttributeTargets.Method, AllowMultiple = false)]
-public class VSOnlyIdeFactAttribute : IdeFactAttribute
+public class ManualRunOnlyIdeFactAttribute : IdeFactAttribute
 {
-    public VSOnlyIdeFactAttribute()
+    public ManualRunOnlyIdeFactAttribute()
     {
-        if (Environment.GetEnvironmentVariable("VisualStudioVersion") is null)
+        if (Environment.GetEnvironmentVariable("CI") is not null)
         {
-            Skip = "This test can only run in Visual Studio";
+            Skip = "This test can only run manually";
         }
     }
 }

src/Razor/test/Microsoft.VisualStudio.Razor.IntegrationTests/StressTests/RCLStressTests.cs

@@ -16,7 +16,7 @@ public class RCLStressTests(ITestOutputHelper testOutputHelper) : AbstractStress
 
     protected override string ProjectZipFile => "Microsoft.VisualStudio.Razor.IntegrationTests.TestFiles.BlazorProjectWithRCL.zip";
 
-    [VSOnlyIdeFact]
+    [ManualRunOnlyIdeFact]
     public async Task AddAndRemoveComponentInRCL()
     {
         await TestServices.SolutionExplorer.OpenFileAsync("RazorClassLibrary", @"Components\RCLComponent.razor", ControlledHangMitigatingCancellationToken);

src/Razor/test/Microsoft.VisualStudio.Razor.IntegrationTests/StressTests/StressTests.cs

@@ -12,7 +12,7 @@ namespace Microsoft.VisualStudio.Razor.IntegrationTests;
 
 public class StressTests(ITestOutputHelper testOutputHelper) : AbstractStressTest(testOutputHelper)
 {
-    [VSOnlyIdeFact]
+    [ManualRunOnlyIdeFact]
     public async Task AddAndRemoveComponent()
     {
         await TestServices.SolutionExplorer.OpenFileAsync(RazorProjectConstants.BlazorProjectName, RazorProjectConstants.CounterRazorFile, ControlledHangMitigatingCancellationToken);