fix test PostSubmitCommentAsAdmin

user was admin when running all tests. (was guest when running alone).
Because of auth.BASIC login user can't logout so we need to mock Auth::check()

mockery/mockery added : run `composer update`

new codeception helper added : run `./codecept build`
[test] guest submitted comment is not published

+use faker
[test] added webhelper amAdmin()

run `./codecept build`
[test] post comment as admin - #2