In component tests, the `within` method is actually an alias to RSpec's
`be_within` matcher, which is used to test numeric ranges. That meant
the tests always passed, even when there were bugs on the page.
In order to use `within` in component tests, we have to use
`page.within`. However, that also fails, since there's no such method
for `Capybara::Node::Simple'` objects, which are used in component
tests.
So we're using `page.find` instead.
See also pull request 945 in https://github.com/github/view_component
