add release pipeline notifications

[rawlingsj]

Current we only seem to be getting slack notifications for Pull Request pipelines. It would also be good to know when a Release pipeline has started, finished but most importantly failed.

[jenkins-x-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.
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/lifecycle stale

[rawlingsj]

/remove-lifecycle stale

[jenkins-x-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.
If this issue is safe to close now please do so with /close.
Provide feedback via https://jenkins-x.io/community.
/lifecycle stale

[jenkins-x-bot]

Stale issues rot after 30d of inactivity.
Mark the issue as fresh with /remove-lifecycle rotten.
Rotten issues close after an additional 30d of inactivity.
If this issue is safe to close now please do so with /close.
Provide feedback via https://jenkins-x.io/community.
/lifecycle rotten

[msvticket]

I get messages for release jobs. I have configured jx-slack to only notify for this, so maybe it fails in some other case.