[6.11.z] added test coverage for clone host-group

[Satellite-QE]

Cherrypick of commit: ff75441676368405b1e73029b23722fb61408c1e

PR Description

Added the test coverage for the clone host group as bz 2122261

Dependency

Airgun PR : https://github.com/SatelliteQE/airgun/pull/773

Test Result

Launching pytest with arguments -k test_positive_clone_host_groups /Users/okhatavk/satellite/robottelo/tests/foreman/ui/test_hostgroup.py --no-header --no-summary -q in /Users/okhatavk/satellite/robottelo

============================= test session starts ==============================
collecting ... collected 7 items / 6 deselected / 1 selected

tests/foreman/ui/test_hostgroup.py::test_positive_clone_host_groups 

=========== 1 passed, 6 deselected, 25 warnings in 246.58s (0:04:06) ===========

[Gauravtalreja1]

trigger: test-robottelo pytest: -k test_positive_clone_host_groups tests/foreman/ui/test_hostgroup.py airgun: 777