Error Tracking feature addition: Notification on new Errors via E-Mail/Webhook

Proposal

As a maintainer I would like to receive a notification on newly occurred errors when using the GitLab integrated error tracking. On smaller projects I'm using the internal error tracking as lightweight sentry alternative, which is great. As mentioned in the initial issue #329596 (closed) under "Good to have improvements" I really would like to see this implemented.

Details

Notification could be done via

• e-Mail: For new errors, configurable via the user or GitLab wide notification templates. As existing errors are already stacked together, this this be no problem. For too noisy apps an automatic throttling policy would be great
• GitLab Issue: A new GitLab issue could automatically be created as an optional feature - using a pre-defined issue template the notification configuration from existing issue templates could be easily used
• webhook: As a plus a Notification via webhook for automatic processing would be a nice add-on.