Test for template hints
Test for template hints

This commit extends the tests to not only look at the name of the
displayed templates and folders, but also the hint text underneath.

Because there are going to be more variations of this hint text in the
future we need to make sure it’s tested.

Doing this in its own commit so only the meaningful changes show up in
the commits that actually change stuff.

alphagov/notifications-admin,alphagov/notifications-admin,alphagov/notifications-admin,alphagov/notifications-admin