Add unit test ensuring that for multiple scenarios of the same name, only 0 or 1 can actually match
Problem: our unit tests don't catch stuff like this:
@rhel-8
@scen_id
Scenario: blah
@rhel+=8
@scen_id
Scenario: blah
This means that outside of RHEL or CentOS, both will match causing run/runtest.sh
give up. To avoid need for further fixes stuff like !1492 (merged), we need an unit test for this.