install-deps: Update Pyyaml version

Move to 6.0.1 to overcome https://github.com/yaml/pyyaml/issues/601

Fixes: https://tracker.ceph.com/issues/63591
Signed-off-by: Brad Hubbard <bhubbard@redhat.com>
(cherry picked from commit 7863d297eaf03a57ce910ab7f7a08e22789ed8d8)

Merge pull request #64748 from kshtsk/wip-72328-reef

reef: qa/tasks/ceph_manager: population must be a sequence