Spinnaker-Backend - Remove pipeline from Spinnaker give a name change - planning

[eyal-mor]

Give a name change, pipelines will remain orphaned in an application.
This could cause confusion or worse, a trigger of the wrong pipeline may produce inconsistent application states in prod.

To mitigate these problems we must be able to remove unused pipelines during the save command.

Plan out the implications of such a "fix" and a mitigation for the possible errors.