Allow setting of caseworking on a user

This commit changes the form that the user sees when inviting or editing
another user, if the service has the ‘caseworking’ permission set.

This will allow creating a new type of user, one who only has the
`send_messages` permission, without the `view_activity` permission.

We are doing this because we think there are a number of services with a
lot of users who don’t need to see the dashboard, or the other team
members, and that we can make a simpler interface for these users.

tests/app/main/views/test_accept_invite.py

@@ -24,7 +24,7 @@ def test_existing_user_accept_invite_calls_api_and_redirects_to_dashboard(
     mocker,
 ):
     expected_service = service_one['id']
-    expected_permissions = {'send_messages', 'manage_service', 'manage_api_keys'}
+    expected_permissions = {'view_activity', 'send_messages', 'manage_service', 'manage_api_keys'}
 
     response = client.get(url_for('main.accept_invite', token='thisisnotarealtoken'))
 
@@ -123,7 +123,7 @@ def test_existing_signed_out_user_accept_invite_redirects_to_sign_in(
     mocker,
 ):
     expected_service = service_one['id']
-    expected_permissions = {'send_messages', 'manage_service', 'manage_api_keys'}
+    expected_permissions = {'view_activity', 'send_messages', 'manage_service', 'manage_api_keys'}
 
     response = client.get(url_for('main.accept_invite', token='thisisnotarealtoken'), follow_redirects=True)
 
@@ -401,7 +401,7 @@ def test_new_invited_user_verifies_and_added_to_service(
 
     # when they post codes back to admin user should be added to
     # service and sent on to dash board
-    expected_permissions = {'send_messages', 'manage_service', 'manage_api_keys'}
+    expected_permissions = {'view_activity', 'send_messages', 'manage_service', 'manage_api_keys'}
 
     with client.session_transaction() as session:
         new_user_id = session['user_id']