Use osci and tmt for gating

.fmf/version

@@ -0,0 +1 @@
+1

gating.yaml

@@ -1,6 +1,8 @@
 --- !Policy
+
 product_versions:
   - rhel-8
 decision_context: osci_compose_gate
 rules:
-  - !PassingTestCaseRule {test_case_name: baseos-ci.brew-build.tier1.functional}
+  - !PassingTestCaseRule {test_case_name: osci.brew-build.tier0.functional}
+

plan.fmf

@@ -0,0 +1,15 @@
+discover:
+  how: shell
+  dist-git-source: true
+  tests:
+  - name: unit
+    test: |
+      cd $(dirname $TMT_SOURCE_DIR/dnspython-*/tests)
+      rm -rf dns dnspython.egg-info
+      cd tests
+      /usr/libexec/platform-python utest.py
+    require:
+    - python3-dns
+
+execute:
+  how: tmt