Follow up on fix on updating memberships when a contact is deceased

Follow up on fix on updating memberships when a contact is deceased

This removes the now-duplicate call from the Contact edit form & fixes it such that the message would appear
for any logged in action that causes this (notably the 2 ways of editing the contact at the moment.)

Note it might change the way the messages look from one message to more than one - this  feels like
it's arguable enough that it's not worth worrying about