fix: The migrated project has changed number

[alessfg]

Proposed changes

Fix the milestone_pr.yml workflow by replacing the project link.

Checklist

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• I have read the contributing guidelines.
• I have signed the F5 Contributor License Agreement (CLA).
• If applicable, I have added Molecule tests that prove my fix is effective or that my feature works.
• If applicable, I have checked that any relevant Molecule tests pass after adding my changes.
• I have updated any relevant documentation (defaults/main/*.yml, README.md and CHANGELOG.md).