Automating Agile workflows with the gitlab-triage gem

Introduces the `gitlab-triage` gem, a Ruby library for automating Agile workflows by interacting with the GitLab API. Details installation, API token retrieval, defining triage policies in `.triage-policies.yml` (e.g., applying labels, commenting on old issues), and running the bot manually or via GitLab CI/CD schedules. Provides advanced examples using Ruby scripts for custom logic, such as identifying issues assigned to team members outside their project or automatically setting due dates. Offers best practices for policy creation and execution, emphasizing starting simple, testing, monitoring, and using labels for triages.