All tests in bin/tests/system/statschannel/tests-xml.py require libxml2
support to be enabled in BIND 9 at build-time. Instead of applying the
same pytest.mark.skipif() decorator to every test in that file, set the
'pytestmark' global accordingly in order to immediately skip all tests
in tests-xml.py if libxml2 support is not compiled in.
Remove all occurrences of the @pytest.mark.xml decorator (and all
associated code) from the "statschannel" system test as the
xml.etree.ElementTree module is a part of the Python standard library
since Python 2.5 (so checking whether it is available is redundant) and
checking for libxml2 support in the tested BIND 9 build is already
handled by setting the 'pytestmark' global accordingly.
(cherry picked from commit 286b57c7f1)
Michał Kępień
098bd03f7d