Remove re-enter password step from rename organisation

Note that this is copied from the same change made to the rename service
page:
1190e4541b

The original idea behind was to always ask users to re-enter their
password any time:
- we want them to be sure that they want to do what they’re about to do
- we want to be sure it’s really the user trying to do the thing (and
  not someone malicious)

In reality we:
- removed this from the initial place it was added (a descendent of the
  ‘suspend service’ feature)
- only ever added it to the ‘rename service’ and ‘rename organisation’
  features

So in reality it’s not a pattern we have persisted with. Arguably there
are several things you can now do in the admin app without re-entering
your password which are much more high consequence than changing the
service name.

Also, with browser autofill there’s a lot less chance that forcing
someone to re-enter a password really gives much defence against an
unattended laptop, for example.

So this commit removes the need to re-enter your password when renaming
an organisation.

app/navigation.py

@@ -324,7 +324,6 @@ class OrgNavigation(Navigation):
             'organisation_dashboard',
         },
         'settings': {
-            'confirm_edit_organisation_name',
             'edit_organisation_agreement',
             'edit_organisation_billing_details',
             'edit_organisation_crown_status',