RHINENG-11310: update actions/upload-artifact

https://github.blog/changelog/2024-03-07-github-actions-all-actions-will-run-on-node20-instead-of-node16-by-default/

.github/workflows/open_api_spec.yml

@@ -26,7 +26,7 @@ jobs:
     - uses: actions/checkout@v4
     - name: Generate Python client with OpenAPIv3 (docs/v3/openapi.json)
       run: docker run --rm -v ${PWD}/docs/v3:/local:Z openapitools/openapi-generator-cli:v6.0.1 generate -i /local/openapi.json -g python -o /local/client
-    - uses: actions/upload-artifact@v2
+    - uses: actions/upload-artifact@v4
       with:
         name: Python-Client
         path: ${{env.working-directory}}/client