Issue 3522772: Add pager to admin subscriptions view, and other minor fixes
Edit views.view.user_mailman_subscriptions.yml: Add a pager; add a filter to hide users with "unsubscribed" status, remove "unsubscribed" status from exposed filter options, remove remember_roles (exc. auth, anon, admin) from views.view.user_mailman_subscriptions.yml, multiple locations.
Closes #3522772