deps: update python docker tag to v3.12 (#309)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| python | image | minor | `3.11-alpine` -> `3.12-alpine` |

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.gitlab-ci.yml

@@ -13,7 +13,7 @@ pre-commit:
 lint:
   stage: test
 
-  image: python:3.11-alpine
+  image: python:3.12-alpine
   before_script:
     - apk add make bash
     - make venv