Improve security auditing with GitLab Operational Container Scanning

Introduces and demonstrates GitLab's Operational Container Scanning feature, which scans running containers in Kubernetes environments. It details the prerequisites (GitLab Ultimate, Kubernetes cluster, kubectl, helm), the deployment of a sample application, and the connection of a Kubernetes cluster via the GitLab Agent for Kubernetes. The configuration of scanning cadence and target namespaces is explained using the agent's `config.yaml`. The post highlights how scan results, generated by Trivy, are reported back to GitLab's Vulnerability Report for auditing and tracking.