Choose jobs in scheduled pipelines
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### Description
I have a `.gitlab-ci.yml` file that holds two deploy jobs. They deploy to the same machine, but should be executed with different frequencies.
Example: I have one job that deploys backend features and gets deployed once a week. I have another job that I would like to run daily, to deploy my `single page application`. The changes and the rate of evolution of the SPA is higher then the backend.
### Proposal
In the scheduled pipelines screen, when adding a new scheduled job, I would like to:
1. Select the job I want for this schedule;
1. If not selected, run all jobs (as it is today)
### Links / references
issue