[ci] Check failing py_tests.

test/python.yml

@@ -13,10 +13,18 @@ py_tests:
     - !reference [.ci-setup, script]
     - cd $PROJECT_ROOT
     - !reference [default, before_script]
+    - |
+      if [ $EXIT_CODE -eq 1 ]; then
+        sed -i "s/==/!=/g" tests/test_base.py
+      fi
   parallel:
     matrix:
       - PROJECT_ROOT: "test/python-template"
         EXIT_CODE: 0
+      - PROJECT_ROOT: "test/python-template"
+        EXIT_CODE: 1
+  allow_failure:
+    exit_codes: 1
 
 py_lint:
   before_script: