chore(deps): update dependency verify.tunit to 31.21.0 (#137)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

src/Directory.Packages.props

@@ -35,6 +35,6 @@
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.7.0" />
     <PackageVersion Include="Microsoft.Testing.Extensions.CodeCoverage" Version="18.8.0" />
     <PackageVersion Include="TUnit" Version="1.58.0" />
-    <PackageVersion Include="Verify.TUnit" Version="31.20.0" />
+    <PackageVersion Include="Verify.TUnit" Version="31.21.0" />
   </ItemGroup>
 </Project>