need option for automatic delete approval per root deployment

[gberche-orange]

The delete lifecyle currently requires human approval for bosh deployment deletion.

In the context of user-triggered creation and deletion, such human approval does not scale, and will lead to Iaas resources leaks and quota exhaustion. We need an option (e.g. in ci-deployment-overview.yml) to configure a periodic automatic delete approval per root deployment (say every 24 hours), leaving enough time for an emergency undelete manual action upon user request.

[o-orand]

TODO: Remove manual approval

[o-orand]

Workaround: creates a pipeline into paas-template using concourse-pipeline-config feature to trigger the cleanup