qa/cephadm: don't test certain workunits with agent

qa/cephadm: don't test certain workunits with agent

There are a handful of workunits that don't work
with or don't make sense with the agent.
The test for the cephadm timeout only works if
the mgr directly runs ceph-volume inventory which
it won't do with the agent present. The adoption
test is just running direct cephadm commands that
are irrelevant to the agent. The test_orch_cli tests
rely on refresh timings that are different with
the agent running, causing spurious failures.

Signed-off-by: Adam King <adking@redhat.com>