try limiting CI unit testing imports

ci/unit-test.template.yml

@@ -2,10 +2,9 @@
     image: ${REGISTRY_URL}/workspaces/${SERVICE_NAME}:${IMAGE_TAG}
     script:
         - ls -la
-        - pip3 install --upgrade pip
-        - pip3 install -r test-requirements.txt
         - cd ${PATH_PREFIX}${SERVICE_NAME}
-        - python3 -m pytest --cov=${SERVICE_NAME} --cov-report=
+        # use the image's poetry virtual environment and packages
+        - $(poetry env info -p)/bin/pytest --cov=${SERVICE_NAME} --cov-report=
         - mv ./.coverage ${CI_PROJECT_DIR}/.coverage.${SERVICE_NAME}.${CI_COMMIT_SHORT_SHA}
     artifacts:
         paths: