Resend all failed messages since a given time.

Messages that were sent successfully, even if failed initially, are not resent.

A completed task will return a payload like the following:

{
  "id": "qtask_33qen93MNuelBAq1T9G7eHLJRsF",
  "status": "finished",
  "task": "endpoint.recover",
  "data": {
    "messagesSent": 2
  }
}

{
  "id": "qtask_1srOrx2ZWZBpBUvZwXKQmoEYga2"
}