Update poetry version, remove no longer needed environment variables

.gitlab-ci.yml

@@ -16,15 +16,10 @@ build-openapi-scheme:
   stage: build
   image: python:3.10-alpine
   variables:
-    SECRET_KEY: not-a-very-secret-key
-    DJANGO_SETTINGS_MODULE: steering.settings
-    # steering.settings switches to sqlite if the VIRTUAL_ENV environment
-    # variable is present. It’s probably a good idea to refactor this to
-    # something more explicit.
     OPENAPI_JSON: ./public/api.json
   before_script:
     - apk add gcc musl-dev zlib-dev jpeg-dev libmagic
-    - pip install poetry==1.2.1
+    - pip install poetry==1.2.2
     - poetry install --without dev,test --no-root
   script:
     - mkdir public