Bring gating.yaml over from Brew dist-git

Signed-off-by: Troy Dawson <tdawson@redhat.com>

gating.yaml

@@ -0,0 +1,9 @@
+--- !Policy
+product_versions:
+    - rhel-8
+decision_context: osci_compose_gate
+rules:
+    - !PassingTestCaseRule {test_case_name: osci.brew-build.tier0.functional} 
+    # TODO: This is not automated yet and it's not easy to run, so we agreed
+    # with QE we will not run these for 8.1
+    #- !PassingTestCaseRule {test_case_name: manual.sst_platform_storage.lvm2.manual-sts-tier1}