Set file contexts for all of /var/lib/pulp

[ekohl]

This wasn't done in the past to coexist with pulp-selinux (from Pulp 2), but those days are long gone. This also makes it easy to set the correct label on /var/lib/pulp/exports (as Katello does).

I think this addresses https://bugzilla.redhat.com/show_bug.cgi?id=2172833

[evgeni]

For reference, this is the old entry in pulp2:
https://github.com/pulp/pulp/blob/c3b2dd512c68bff929a401c91b2d2c13639c238c/server/selinux/server/pulp-server.fc#L6

[dralley]

This might also address #65 ?

[ekohl]

@dralley I'm not sure. Executing code in /var/lib is uncommon so I'd say the common approach would be to create a specific file context for /var/lib/scripts(/.*)? (like pulpcore_user_script_t) and allow execution of that.