[MIG-485] Document new helper annotations (BSL/VSL owner & original reclaim policy)

[eriknelson]

1.4.0 will be adding two utility annotations that should be documented both upstream and downstream:

1. A customer reported an issue where MTC was installed used a bit, then uninstalled and reinstalled. A previous BSL was still around that contained stale credentials, but it was unclear which install this actually originated from. We've added an annotation to indicate which entity created certain resources so that they can be traced and we can more easily identify a case like this while debugging. Scott Seago Could you fill in the specifics for this one, I'm blanking on exactly which resources would be marked with the relation, and from where. Updated details in comment.

2. From BZ: Bug 1906730 - PV policy has changed after running a migration using the "move" action

We'll create an annotation for any PVC where we modify the policy, but we won't actually modify the policy post-migration. Reverting the policy post-migration brings with it the risk that rollback will delete user data. We don't want that, but we want to provide users with the information necessary to manually restore the pre-migration policy. To do this we want to add an annotation indicating the previous policy any time we modify policy as part of a migration action.

[apinnick]

@eriknelson @sseago
Will this be ready in time for 1.4.0?

[apinnick]

I started downstream documentation. PR: openshift/openshift-docs#28994