update_user now resets failed_login_count if password is changed

until work is done to stop using PUT /user/{id} on the admin app, this
function also needs to reset failed logins, cos it's used during the
forgotten password flow

app/dao/users_dao.py

@@ -114,7 +114,6 @@ def reset_failed_login_count(user):
 
 def update_user_password(user, password):
     # reset failed login count - they've just reset their password so should be fine
-    user.failed_login_count = 0
     user.password = password
     user.password_changed_at = datetime.utcnow()
     db.session.add(user)