Add note about OCS running outside of GitLab CI/CD
What does this MR do and why?
This MR adds clarification to the documentation of Operational Container Scanning to clarify that this feature is working independently from GitLab CI/CD.
MR acceptance checklist
Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.
Related to #458223 (closed)