Expose test artifacts to the Gitlab CI interface

Make tests generate JUnit artifacts and expose them to the Gitlab CI UI.

test/integration-test.yml

@@ -22,16 +22,22 @@
     - name: Run tests
       command: "podman run --rm --network host --mount type=bind,source=/tmp/test-config.yml,destination=/test-config.yml --mount type=bind,source=/artifacts,destination=/artifacts {{ test_image }}"
 
+    - stat:
+        path: "/artifacts/pytest.xml"
+      register: pytest_xml_stat
+
     - name: Retrieve test result
       slurp:
         src: "/artifacts/pytest.xml"
       register: pytest_xml
+      when: "pytest_xml_stat and pytest_xml_stat.exists"
 
     - name: Store test results locally
       local_action:
         module: copy
         dest: "pytest.xml"
         content: "{{ pytest_xml['content'] | b64decode }}"
+      when: "pytest_xml_stat and pytest_xml_stat.exists"
 
   vars:
     test_image: "registry.git.autistici.org/ai3/float:integration-test"