chore(deps): update dependency tunit to 1.21.20 (#404)

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

Author: renovate[bot]

Directory.Packages.props

@@ -17,6 +17,6 @@
     <PackageVersion Include="Microsoft.Testing.Extensions.CodeCoverage" Version="18.5.2" />
     <PackageVersion Include="NetEvolve.Arguments" Version="3.2.84" />
     <PackageVersion Include="NetEvolve.Extensions.TUnit" Version="3.5.3" />
-    <PackageVersion Include="TUnit" Version="1.21.6" />
+    <PackageVersion Include="TUnit" Version="1.21.20" />
   </ItemGroup>
 </Project>