public function signupSuccessfully(FunctionalTester $I)
{
$I->submitForm($this->formId, ['SignupForm[username]' => 'tester', 'SignupForm[email]' => '*****@*****.**', 'SignupForm[password]' => 'tester_password']);
$I->seeRecord('common\\models\\User', ['username' => 'tester', 'email' => '*****@*****.**']);
$I->see('Logout (tester)', 'form button[type=submit]');
}
