Removed a constantly failing call to prepare_host

prepare_host is executed from within each of install_master, install_replica
and install_client in tasks.py anyway, so no need to call it here also.
Besindes this call kept failing when IntegrationTest wes initialized more than
once during the test execution.

https://fedorahosted.org/freeipa/ticket/5723

Reviewed-By: Martin Basti <mbasti@redhat.com>

ipatests/pytest_plugins/integration.py

@@ -30,7 +30,6 @@ from pytest_multihost import make_multihost_fixture
 
 from ipapython import ipautil
 from ipapython.ipa_log_manager import log_mgr
-from ipatests.test_integration import tasks
 from ipatests.test_integration.config import Config
 from ipatests.test_integration.env_config import get_global_config
 
@@ -197,8 +196,6 @@ def mh(request, class_integration_logs):
     print(mh.config)
     for host in mh.config.get_all_hosts():
         host.add_log_collector(collect_log)
-        cls.log.info('Preparing host %s', host.hostname)
-        tasks.prepare_host(host)
 
     setup_class(cls, mh)
     mh._pytestmh_request.addfinalizer(lambda: teardown_class(cls))