Sub workspaces cause content stability issues

Problem/Motivation

Sub workspaces cause issues if they have content in them that is not merged back to a parent before the parent is published.

Steps to reproduce

If someone creates a workspace, October changes. Then someone else creates weekly sub-workspaces. October Week 1, 2, 3 , 4. Then forgets to merge one of the sub spaces back into the parent workspace before the parent workspace is published... the content is left in an unstable state. It is locked by a sub workspace that already had its content all published when the parent was published.

Proposed resolution

There isn't any "status" on a workspace in core to block publishing the parent if there are non published sub workspaces. I think we have to somehow publish all the children when a parent is also published.

Remaining tasks

User interface changes

Introduced terminology

API changes

Data model changes

Release notes snippet