t: Extend unit-test for WebAPI::Auth::OpenID

Tested with

```
rm -rf cover_db/ && cover -coverage stmt -test -make 'prove -Ilib t/03-auth-openid.t; echo 0' && html2text cover_db/lib-OpenQA-WebAPI-Auth-OpenID-pm.html
```

this can be used to extend further and cover more paths.

t/03-auth-openid.t

@@ -10,14 +10,23 @@ use lib "$FindBin::Bin/lib", "$FindBin::Bin/../external/os-autoinst-common/lib";
 use OpenQA::Test::TimeLimit '10';
 use OpenQA::WebAPI::Auth::OpenID;
 
+
 is OpenQA::WebAPI::Auth::OpenID::_first_last_name({'value.firstname' => 'Mordred'}), 'Mordred ',
   '_first_last_name concats also with empty fields';
-my $openid = OpenQA::WebAPI::Auth::OpenID->new();
 my (%openid_res, %openid_res2);
 my $vident = Test::MockObject->new->set_series('signed_extension_fields', \%openid_res, \%openid_res2);
 $vident->{identity} = 'mordred';
-my $mock = Test::MockModule->new('OpenQA::WebAPI::Auth::OpenID');
-$mock->noop('_create_user');
-$mock->mock('session', {});
-ok $openid->_handle_verified($vident), 'can call _handle_verified';
+my $users = Test::MockObject->new->set_always('create_user', 1);
+my $schema = Test::MockObject->new->set_always(resultset => $users);
+my %session;
+my $c
+  = Test::MockObject->new->set_always(schema => $schema)->set_always(session => \%session)->set_true('_create_user');
+ok OpenQA::WebAPI::Auth::OpenID::_handle_verified($c, $vident), 'can call _handle_verified';
+$c->set_always(
+    req => Test::MockObject->new->set_always(params => Test::MockObject->new->set_always(pairs => [1, 2]))
+      ->set_always(url => Test::MockObject->new->set_always(base => 'openqa')))
+  ->set_always(app => Test::MockObject->new->set_always(config => {})
+      ->set_always(log => Test::MockObject->new->set_true('error', 'debug')))->set_true('flash');
+is OpenQA::WebAPI::Auth::OpenID::auth_response($c), 0, 'can call auth_response';
+
 done_testing;