fix: backend/quart_api/Dockerfile.slim.multi-stage to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-DEBIAN12-SQLITE3-6139924
- https://snyk.io/vuln/SNYK-DEBIAN12-ZLIB-6008963
- https://snyk.io/vuln/SNYK-DEBIAN12-OPENSSL-7411350
- https://snyk.io/vuln/SNYK-DEBIAN12-OPENSSL-7411350
- https://snyk.io/vuln/SNYK-DEBIAN12-OPENSSL-8229893

Author: snyk-bot

backend/quart_api/Dockerfile.slim.multi-stage

@@ -1,4 +1,4 @@
-FROM python:3.8-slim as builder
+FROM python:3.13.2-slim as builder
 
 RUN DEBIAN_FRONTEND=noninteractive apt-get update && \
     apt-get -y upgrade && \
@@ -17,7 +17,7 @@ RUN POETRY_VIRTUALENVS_CREATE=false poetry install --no-dev
 
 
 
-FROM python:3.8-slim as final
+FROM python:3.13.2-slim as final
 
 COPY --chown=nobody:nogroup --from=builder /venv /venv
 ENV PATH=/venv/bin:${PATH}