Update fixtures for responsediff 0.6

...esponse_fixtures/DossiersTest.test_dossier_detail.content

...sponse_fixtures/DossiersTest.test_dossier_detail.metadata

.../response_fixtures/DossiersTest.test_dossier_list.content

...response_fixtures/DossiersTest.test_dossier_list.metadata

...nse_fixtures/GroupListTest.test_active_committees.content

...se_fixtures/GroupListTest.test_active_committees.metadata

...se_fixtures/GroupListTest.test_active_delegations.content

...e_fixtures/GroupListTest.test_active_delegations.metadata

...sponse_fixtures/GroupListTest.test_active_parties.content

...ponse_fixtures/GroupListTest.test_active_parties.metadata

...sponse_fixtures/GroupListTest.test_all_committees.content

...ponse_fixtures/GroupListTest.test_all_committees.metadata

...ponse_fixtures/GroupListTest.test_all_delegations.content

...onse_fixtures/GroupListTest.test_all_delegations.metadata

.../response_fixtures/GroupListTest.test_all_parties.content

...response_fixtures/GroupListTest.test_all_parties.metadata

...sts/response_fixtures/GroupListTest.test_chambers.content

...ts/response_fixtures/GroupListTest.test_chambers.metadata

...ests/response_fixtures/GroupListTest.test_country.content

...sts/response_fixtures/GroupListTest.test_country.metadata