rhissue_tests: do not run commit policy checks on linked issues

Linked issues are never listed in the commit log to use for dist-git gating checks, so their commit policy evaulation bits don't actually matter, and it's very confusing for people to see evaluation failures during the blocker/exception phase on their Tasks. They should only have to get b/e for their main issue for things to look clean. The simple fix here is to simply not run commit policy checks on linked testing tasks, as we've got several other tests to cover all the other relevant bits.

Fixes: KMAINT-1281

Signed-off-by: Jarod Wilson jarod@redhat.com