Simplify emulating last_sign_in_at
Simplify emulating last_sign_in_at

We were updating the database after starting the browser to emulate the
behavior where a user logs in a day before the current request. We can
use `current_sign_in_at` instead and devise will automatically copy that
value to `last_sign_in_at` after users visit a page.

This way we avoid setting up the database after the process runnin the
browser has been started.

consul/consul,consul/consul,consul/consul,consul/consul,consul/consul