Add option on the approval type to decide if the set of approvals needs to be an AND or an OR

Problem/Motivation

While a reviewer can be required or optional, there isn't any toggle presently for marking how many of the required reviewers must approve before something is unblocked. For an MVP, that's OK. Everyone has to approve to unblock. But wouldn't it be nice to make that an option so if 3 reviewers are added, only one of them has to approve?

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes