refs and cleanup

Author: SimonCropp

src/Directory.Packages.props

@@ -5,17 +5,17 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageVersion Include="MarkdownSnippets.MsBuild" Version="28.0.0-beta.7" />
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.0.1" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
     <PackageVersion Include="NUnit" Version="4.4.0" />
     <PackageVersion Include="NUnit3TestAdapter" Version="5.2.0" />
-    <PackageVersion Include="Polyfill" Version="8.9.1" />
+    <PackageVersion Include="Polyfill" Version="9.0.1" />
     <PackageVersion Include="ProjectDefaults" Version="1.0.162" />
     <PackageVersion Include="SixLabors.ImageSharp" Version="3.1.12" />
-    <PackageVersion Include="Verify" Version="31.5.3" />
+    <PackageVersion Include="Verify" Version="31.6.0" />
     <PackageVersion Include="Verify.DiffPlex" Version="3.1.2" />
     <PackageVersion Include="Verify.Http" Version="7.4.0" />
     <PackageVersion Include="Verify.ImageMagick" Version="3.8.0" />
-    <PackageVersion Include="Verify.NUnit" Version="31.5.3" />
+    <PackageVersion Include="Verify.NUnit" Version="31.6.0" />
     <PackageVersion Include="Microsoft.Sbom.Targets" Version="4.1.3" />
   </ItemGroup>
 </Project>