Make the new notification for project deletion optional

Problem

Recently Notify users that their project or group is queued for deletion added a email notification for queued project deletion.

I have a GitLab Ultimate customer (ZD internal ticket) requesting the ability to select a notification level for this new feature. Currently it is on with no ability to adjust it. Due to some automation this is causing a large influx of emails regarding the deletion events.

Proposal

The proposal is to add some level of customization to where this feature is enabled. The customer would like the ability to turn this off per group and the projects in those groups.

Another option would be to make these notifications part of the product, rather than using email notifications.

Design

TBD