🔥(helm) remove useless footer config

Remove:
- FRONTEND_FOOTER_FEATURE_ENABLED
- FRONTEND_FOOTER_URL

Author: AntoLC

src/helm/env.d/dev/values.impress.yaml.gotmpl

@@ -50,8 +50,6 @@ backend:
     DB_USER: dinum
     DB_PASSWORD: pass
     DB_PORT: 5432
-    FRONTEND_FOOTER_FEATURE_ENABLED: true
-    FRONTEND_URL_JSON_FOOTER: https://impress.127.0.0.1.nip.io/contents/footer-demo.json
     POSTGRES_DB: impress
     POSTGRES_USER: dinum
     POSTGRES_PASSWORD: pass