Give users/groups permission to scan Gitlab group

### Dependencies

### Feature Request

Sometimes the Gitlab webhook isn't sufficient to trigger the job creation. For example, the repository is created without a Jenkinsfile, so the job isn't created and no webhooks are configured to notify Jenkins when the Jenkinsfile is pushed (it wouldn't make any sense). So I want to give my users the power to force Scan when they need instead of reducing polling frequency. Ideally, I would be able to give this permission to certain user logins or groups.