TEST: Add ptmcmcsampler back to test images

It looks like PTMCMCSampler got accidentally removed when we added the py310 tests in.

.gitlab-ci.yml

@@ -251,8 +251,10 @@ pages:
   stage: deploy
   image: docker:20.10.12
   needs: ["containers"]
-  only:
-    - schedules
+  rules:
+    - changes:
+        - containers/*
+    - if: $CI_PIPELINE_SOURCE == "schedule"
   script:
     - cd containers
     - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY