Improve fiware migration tests mocking idm integration settings.
Improve fiware migration tests mocking idm integration settings.

This make possible running fiware migration tests also when the IdM
integration is disabled.

rockneurotiko/wirecloud,rockneurotiko/wirecloud,jpajuelo/wirecloud,jpajuelo/wirecloud,rockneurotiko/wirecloud,jpajuelo/wirecloud,jpajuelo/wirecloud,rockneurotiko/wirecloud