Upgrade to System.CommandLine beta6 - the latest available on nuget.org

Co-authored-by: BenjaminMichaelis <22186029+BenjaminMichaelis@users.noreply.github.com>

Author: Copilot

Directory.Packages.props

@@ -10,7 +10,7 @@
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
     <PackageVersion Include="Polly" Version="8.6.3" />
-	<PackageVersion Include="System.CommandLine" Version="2.0.0-beta5.25306.1" />
+	<PackageVersion Include="System.CommandLine" Version="2.0.0-beta6.25358.103" />
     <PackageVersion Include="xunit" Version="2.9.3" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.4" />
   </ItemGroup>