This adds a test that automates
https://fedoraproject.org/wiki/QA:Testcase_Clevis. It requires
os-autoinst-4.6-18.20200623git5038d8c or newer, and a worker
host in the 'tpm' class which is set up to have an instance of
swtpm running at /tmp/mytpmX , where X is the worker instance
number, for each worker. The Fedora infrastructure ansible
plays have been updated to handle this via an instantiated
systemd service, which other instances can also adopt.
Signed-off-by: Adam Williamson <awilliam@redhat.com>