feat(scheduler): allow custom payload with manual trigger

[kerwanp]

Description

This pull-request adds the ability to provide a custom payload when doing manual schedule trigger.

const schedule = await Schedule.find(scheduleId)
await schedule.trigger(customPayload)

Note

The job payload type is not available here. In the future it could be interesting to have the API available directly on the job itself to have proper typing:

const schedule = await MyJob.findSchedule(scheduleId)
await schedule.trigger(customPayload)

[RomainLanz]

Thanks!