Change:
- Remove check that states that only Fedora can be an OSTree
distribution.
- This allows us to correctly return "atomic_container" as the pkg_mgr
fact for RHEL for Edge, Fedora/RHEL/CentOS Atomic Host, etc.
Test Plan:
- Created local RHEL for Edge image and tested against it.
- Tested against regular RHEL 8 and still got `dnf` as expected.
- Tested against RHEL 7 Atomic Host and got `atomic_container` now.
- New unit tests.
Tickets:
- Fixes#73084
Signed-off-by: Rick Elrod <rick@elrod.me>
