Modernize base Docker image

This commit migrates the StreamFlow Docker image from Python 3.11
to Python 3.13 and from Alpine 3.16 to Alpine 3.21

Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.11-alpine3.16 AS builder
+FROM python:3.13-alpine3.21 AS builder
 ARG HELM_VERSION
 
 ENV VIRTUAL_ENV="/opt/streamflow"
@@ -38,7 +38,7 @@ RUN apk --no-cache add \
     && python -m venv ${VIRTUAL_ENV} \
     && pip install .
 
-FROM python:3.11-alpine3.16
+FROM python:3.13-alpine3.21
 LABEL maintainer="[email protected]"
 
 ENV VIRTUAL_ENV="/opt/streamflow"