Implement periodic workflows
User story
As a workspace owner, I want to be able to create workflow templates that will trigger regular execution of the corresponding workflow. The frequence of execution should be defined in cron-like manner.
It will be particularly useful for UpdateEnvironments workflows but will likely also be useful for other workflows (like UpdateSuites where we want to refresh the metadata timestamp on a regular basis).
Implementation plan
See WIP design here: !1087
Notes
This issue description can be modified to integrate feedback from comments and from associated merge requests.