Description of problem:

If you use the "hammer content-view version export" command and attempt to export a CV containing only a puppet repo and nothing else, you'll get an error.

See https://bugzilla.redhat.com/show_bug.cgi?id=1285244#c98

"""
I just updated to Snap 20.0
I created new CV with some Errata RPMs and one Puppet module, published, and the export worked OK.

Then, just for fun, I created another CV with just a Puppet module, published that, ran the export command:

[Foreman] Password for admin:
[..........] [50%]
Error: unknown file type: /var/lib/pulp/published/yum/master/group_export_distributor/Default_Organization-TestViewPuppetOnly-v1.0
[root@rhel7-2-sat6-2 ~]#

as I have self made modules I changed to anther module but still got error:
[Foreman] Password for admin:
[............................] [100%]
Error: unknown file type: /var/lib/pulp/published/yum/master/group_export_distributor/Default_Organization-TestViewPuppetOnly-v2.0
[root@rhel7-2-sat6-2 ~]#

"""

Version-Release number of selected component (if applicable): snap 20.0