Move workaround to properties file

Move CA2252 workaround to the props file instead of the code.

Author: martincostello

Directory.Build.props

@@ -22,7 +22,12 @@
   <ItemGroup>
     <Compile Include="$(MSBuildThisFileDirectory)GlobalUsings.cs" />
   </ItemGroup>
-  <!-- HACK Various work arounds until Visual Studio works with latest language features -->
+  <!-- HACK Various workarounds that affect the CLI and the IDE -->
+  <PropertyGroup>
+    <!-- HACK Workaround warning in xunit collections -->
+    <NoWarn>$(NoWarn);CA2252</NoWarn>
+  </PropertyGroup>
+  <!-- HACK Various workarounds until Visual Studio works with latest language features -->
   <PropertyGroup Condition="'$(BuildingInsideVisualStudio)' == 'true'">
     <LangVersion>preview</LangVersion>
     <!-- HACK Workaround for https://github.com/dotnet/roslyn/issues/54255 -->

tests/TodoApp.Tests/HttpServerCollection.cs

@@ -3,11 +3,9 @@
 
 namespace TodoApp
 {
-#pragma warning disable CA2252 // HACK Appears to be a bug - investigate in a later preview build
     [CollectionDefinition(Name)]
     public sealed class HttpServerCollection : ICollectionFixture<HttpServerFixture>
     {
         public const string Name = "TodoApp HTTP server collection";
     }
-#pragma warning restore CA2252
 }

tests/TodoApp.Tests/TodoAppCollection.cs

@@ -3,11 +3,9 @@
 
 namespace TodoApp
 {
-#pragma warning disable CA2252 // HACK Appears to be a bug - investigate in a later preview build
     [CollectionDefinition(Name)]
     public sealed class TodoAppCollection : ICollectionFixture<TodoAppFixture>
     {
         public const string Name = "TodoApp server collection";
     }
-#pragma warning restore CA2252
 }