We've got quite a messy hack to sign in managers: they need to visit a
specific URL (management root path).
That means tests signing in managers start the browser to sign them in,
which might cause issues if we setup the database after that.
By using real XML responses developers will be able to understand better
how the integration works (the data flow), and the correspondency between
`remote_census` settings and their place at a real XML response.
As `stubbed_responses` methods were removed from the model layer now the
stubbing part should be managed from the test environment code so also
added a new helper module `RemoteCensusSetup` that can be used anywhere
where we need to call the web service.
Co-Authored-By: Javi Martín <javim@elretirao.net>
