When re-retrieving hook tasks from the DB double check if they have not
been delivered in the meantime. Further ensure that tasks are marked as
delivered when they are being delivered.
In addition:
* Improve the error reporting and make sure that the webhook task
population script runs in a separate goroutine.
* Only get hook task IDs out of the DB instead of the whole task when
repopulating the queue
* When repopulating the queue make the DB request paged
Ref #17940
Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
787f6c3227