HELP-76156 requested backports of SERVER-69418  to v7 and v8 because they were still able to add more than 7 voting members. Backport was declined pending investigation into whether existing clusters with > 7 voting members would be affected by this backport:

1. If a set has 9 members and attempts to add another, is it rejected during reconfig?
2. If a set has 9 members and attempts to remove one (which it would have to do if this was backported), does it get rejected during reconfig since it's still above 7?