fix: test case helper missing auth

[jlopes90]

https://github.com/codeigniter4/shield/blob/c48cb81bd80762e0133d1ba53f50e16ab99c1f6e/tests/_support/TestCase.php#L28

to

helper(['auth', 'setting']);

To confirm that it is correct?

[kenjis]

Run composer update.

[kenjis]

@jlopes90 See #368 Now we don't need to load auth_helper and email_helper, because Composer autoloads them.