remove notifications for redeemed/auto-deleted channels
context
- when we were first building the auto-delete feature, it was helpful to be notified when people redeemed their channels and/or channels were deleted (1) to make sure the timing aspects of the feature worked as expected, (2) to get a sense of what percentage of people redeemed their channels
- now that we know the feature works, the notifications deliver less value. since we prompt admins to delete their channels more frequently (every week), we also get a lot of low-value notifications, leading to alert fatigue
- this MR removes the notifications to reduce alert fatigue but leaves work on replacing notifications with metrics to a later card
behavior
GIVEN a channel that has been scheduled for auto-deltion
- WHEN the channel is redeemed or auto-deleted
- THEN that fact is logged but nobody is notified
out-of-scope
- replacing notifications with metrics counters. that is left for #405