CI: C# code linting
Add a GitLab Action configuration that will run linting on all C# files in the project on every push and merge request. If code contains styling errors, the Action should fail blocking merge requests with code style problems.
Add a GitLab Action configuration that will run linting on all C# files in the project on every push and merge request. If code contains styling errors, the Action should fail blocking merge requests with code style problems.