With the new unique parameter added in the action scheduler 3.5.0 the
as_schedule_single_action that schedules an immediate action
seems to be more convenient for the action scheduler.
We get better control over the scheduling of subsequent runs.
Note: We don't want to use the async action that is also executed immediately,
but it has the highest priority and we don't want to block actions scheduled by other plugins.
[MAILPOET-4684]
We had some cases of multiple triggers created most probably because of a race conditions.
The unique action functionality added in the action scheduled 3.5.0 should prevent it.
[MAILPOET-4684]
This will cancel all jobs with one query. Instead of cancelling one by one.
In case that some action gets scheduled multiple times e.g. due a race condition
it will remove all jobs.
