Automatic E2E Tests

[tnorimat]

JIRA ticket : KEYCLOAK-9359

[tnorimat]

It has been confirmed as preliminary analysis that Web Authentication Testing API can be integrated into keycloak's Arquillian integration testing framework and basic functional tests of registration and authentication flow has been realized. However, the following problems are found :

• can not write Arquillian integration test on this project
  I do not know how to write Arquillian integration test on this project leveraging integration-arquillian-tests-base project (I tried but failed).
  Therefore, I've implemented this webauthn's feature integration test onto keycloak project itself by porting this project onto keycloak project itself. It worked well.
  This problem is not critical because eventually this webauthn's feature be implemented as a sub-project of keycloak itself.

• test coverage
  Using Web Authentication Testing API, I can not manipulate the responses of both navigator.credentials.create() and .get(). Therefore, I can not test several code paths of this webauthn's feature.
  I know that webauthn4j has some emulators that I can manipulate responses of those APIs freely but it seems that these emulators can not be used under Arquillian integration tests.