docs(guide): add deduplication of jobs using schedulers

[roggervalf]

Why

1. Why is this change necessary? When someone ones to combine job scheduler logic with deduplication, there is a way to do it without breaking these iterations

How

1. How did you implement this? Provide a pattern

Additional Notes (Optional)

ref #3165

[manast]

Something must be missing in this example because it currently does not make a lot of sense to me. You are adding a standard job with a deduplication id, and then a job scheduler with no relation to the previous job nor the deduplication id.

[roggervalf]

so the job scheduler, works as a producer for a job to be deduplicated. We cannot deduplicate a job generated by a job-scheduler, but if this generated job produce a new job, this one can be deduplicated

[manast]

I think the text needs to be improved then to explain this in detail. I do not think it is important to mention this last sentence: "but if this generated job produce a new job, this one can be deduplicated", as this is nothing particular to repeatable jobs or anything, it is trivial that you can add new jobs to any queue from the process function and therefore use any options you want including deduplicationId