Update debian Docker tag to v12 (#115)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| debian | final | major | `11.7-slim` -> `12.1-slim` |

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Dockerfile

@@ -68,7 +68,7 @@ RUN mix do phx.gen.release, release
 ## **********************************************************************
 ## Run release in production mode
 ## **********************************************************************
-FROM debian:11.7-slim as deploy
+FROM debian:12.1-slim as deploy
 LABEL maintainer="Ilkka Poutanen <ilkka@ilkka.dev>"
 RUN apt-get update \
   && export DEBIAN_FRONTEND=noninteractive \