Adjust the gating tests for Python 3.12 @ RHEL 8

gating.yaml

@@ -1,8 +1,6 @@
 --- !Policy
 product_versions:
-  - fedora-*
-decision_contexts:
-  - bodhi_update_push_testing
-  - bodhi_update_push_stable
+  - rhel-8
+decision_context: osci_compose_gate
 rules:
-  - !PassingTestCaseRule {test_case_name: fedora-ci.koji-build./plans/smoke.functional}
+  - !PassingTestCaseRule {test_case_name: osci.brew-build.tier0.functional}

plans/smoke.fmf

@@ -4,9 +4,9 @@ discover:
   tests:
     - name: /smoke/import-python-module
       test: |
-        python3 -c 'import importlib as il; print(il.import_module("lxml"))'
+        python3.12 -c 'import importlib as il; print(il.import_module("lxml"))'
     - name: /smoke/etree-fromstring
       test: |
-        python3 plans/etree-fromstring.py
+        python3.12 plans/etree-fromstring.py
 execute:
   how: tmt