chore(deps): update python docker tag to v3.15.1 (#38)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| python | final | minor | `3.14.8-alpine` -> `3.15.1-alpine` |
| python | stage | minor | `3.14.8-alpine` -> `3.15.1-alpine` |

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Reviewed-on: #38

Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.14.8-alpine AS builder
+FROM python:3.15.1-alpine AS builder
 
 WORKDIR /app
 
@@ -7,7 +7,7 @@ RUN apk add --no-cache gcc musl-dev jpeg-dev zlib-dev
 COPY requirements.txt .
 RUN pip wheel --no-cache-dir --wheel-dir=/wheels -r requirements.txt
 
-FROM python:3.14.8-alpine AS base
+FROM python:3.15.1-alpine AS base
 
 WORKDIR /app