Bump python from 3.14.1-alpine3.21 to 3.15.0a2-alpine3.21 - #32

buildx failed with: ERROR: failed to build: failed to solve: process "/bin/sh -c pip install --no-cache-dir --no-warn-script-location --user -r /tmp/requirements.txt && rm -f /tmp/requirements.txt" did not complete successfully: exit code: 1