ci: adjust schedules
With Gitlab 10.7 variable support in pipeline only/except, it's now possible to execute OBS builds with a nightly schedule, while keeping the docker image builds on a weekly schedule.
https://docs.gitlab.com/ee/ci/variables/#variables-expressions
- nightly pipeline example: https://gitlab.labs.nic.cz/knot/knot-dns/pipelines/36819
- weekly pipeline example: https://gitlab.labs.nic.cz/knot/knot-dns/pipelines/36818
From what I understand, it's not possible to combine variable-triggered pipelines with other kinds (branches, triggers, ...) - so I had to remove the manual trigger. Is anyone using that?
If not, we can just omit it. Manual re-build can be done by clicking a button in https://gitlab.labs.nic.cz/knot/knot-dns/pipeline_schedules
Otherwise, we'd have to figure out if it's possible to provide variables within the trigger.
