Update python:3.12-slim-bullseye Docker digest to 957e8c5 (#243)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| python | final | digest | `34ba6fe` -> `957e8c5` |

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/lettuce-financial/github-bot-signed-commit).

<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzOC45Ny4wIiwidXBkYXRlZEluVmVyIjoiMzguOTcuMCIsInRhcmdldEJyYW5jaCI6Im1haW4iLCJsYWJlbHMiOltdfQ==-->

Dockerfile

@@ -1,5 +1,5 @@
 ### Use an appropriate version of Python
-FROM python:3.12-slim-bullseye@sha256:34ba6fe9564c84d5f9252cbfff93f20e1ca325fa89d02cb0eb72ad73663c2314 AS python
+FROM python:3.12-slim-bullseye@sha256:957e8c5f7483515a988d27b18da7ec2b2648005df9bcbaaba781df3fdca0d055 AS python
 
 ENV DEBIAN_FRONTEND=noninteractive