Bump System.CodeDom from 5.0.0 to 6.0.0

Bumps [System.CodeDom](https://github.com/dotnet/runtime) from 5.0.0 to 6.0.0.
- [Release notes](https://github.com/dotnet/runtime/releases)
- [Commits](dotnet/runtime@v5.0.0...v6.0.0)

---
updated-dependencies:
- dependency-name: System.CodeDom
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

src/PublicApiGenerator/PublicApiGenerator.csproj

@@ -17,7 +17,7 @@
   <ItemGroup>
     <PackageReference Include="MinVer" Version="2.5.0" PrivateAssets="All" />
     <PackageReference Include="Mono.Cecil" Version="0.11.4" />
-    <PackageReference Include="System.CodeDom" Version="5.0.0" />
+    <PackageReference Include="System.CodeDom" Version="6.0.0" />
   </ItemGroup>
 
 </Project>