Add gating on dist-git tests

This patch adds gating on dist-git tests available in the repository
For more information see: https://url.corp.redhat.com/dist-git-gating-rhel8
Contact: #osci

Signed-off-by: Miroslav Vadkerti <mvadkert@redhat.com>

gating.yaml

@@ -0,0 +1,6 @@
+--- !Policy
+product_versions:
+  - rhel-8
+decision_context: osci_compose_gate
+rules:
+  - !PassingTestCaseRule {test_case_name: baseos-ci.brew-build.tier1.functional}