tests: remove misleading docstrings on libvirt tests
tests: remove misleading docstrings on libvirt tests

These docstrings take precedence over the method name,
to identify the test in the results.  So just remove
these misleading docstrings as they don't give extra
info over the method name itself.

Change-Id: I4c415f8c4be588f5de751ab8e4d21e85a18f6b75

n0ano/ganttclient