Scheduled pipeline execution policies are GA

Scheduled pipeline execution policies are now generally available. Define a schedule once in a security policy project and enforce it across every project in scope, without editing each project's .gitlab-ci.yml. If requirements change, update the policy in one place instead of coordinating changes across many CI/CD configuration files.

Use scheduled policies to run compliance scripts, security scans, or other custom CI/CD jobs on a daily, weekly, or monthly cadence, independent of commit activity. This is useful for repositories without regular code changes, such as running dependency scans to detect newly discovered vulnerabilities. Each policy runs as a separate pipeline, with time zone support, time window distribution, and branch targeting.