broken journal and filestore data size in `lvm batch --report`
When running ceph-volume lvm batch --report --filestore $devices the journal size and data size were being reported as the repr of the size class (e.g. "size": <FloatB(7516192768.0)>). This was causing JSON parsing issues as well as not being friendly to the reader of the report.
This also includes some testing changes that make our functional tests fail fast and saves some time by only running the ceph-common role from ceph-ansible once during testing.