gating.yaml : bring up-to-date wrt requirements
1) Update the testcase name. This is a global fedora-wide
change instituted May 2020
2) Add a 'subject_type' line. This seems to be a global
change instituted Augist 2019, but I never heard about it
3) Revert decision_context from 'stable' to 'testing'.
This was an accidental holdover from when we branched
master to f32. Steps will be taken to ensure this
doesn't happen on f33.
Signed-off-by: Ed Santiago <santiago@redhat.com>