Removing a pipeline in OSIO does not remove the endpoints deployed by that pipeline

[ldimaggi]

Related to: #2629

Steps to recreate:

• Create a new quickstart
• Observe the build pipeline runs to completion and deploys to stage and run
• Verify that the quickstart's endpoints are available
• Delete the build pipeline
• Verify that the quickstart's endpoints are still available

At this point, the user cannot initiate a new build for the quickstart. We should give the user the option to have the deployments removed when the build pipeline is removed.

[joshuawilson]

This is either a duplicate or an expansion of #1746

[ldimaggi]

Closing - issue is no longer seen.