fix: Dockerfile to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-ALPINE317-EXPAT-6241042
- https://snyk.io/vuln/SNYK-ALPINE317-SQLITE-6179510
- https://snyk.io/vuln/SNYK-ALPINE317-BUSYBOX-7254940
- https://snyk.io/vuln/SNYK-ALPINE317-BUSYBOX-7254941
- https://snyk.io/vuln/SNYK-ALPINE317-BUSYBOX-7254941

Dockerfile

@@ -1,5 +1,5 @@
 # vim:set ft=dockerfile:
-FROM python:3.11-alpine3.17
+FROM python:3.13.0a2-alpine3.17
 LABEL Description="Twitcher" Vendor="Birdhouse" Maintainer="https://github.com/bird-house/twitcher"
 
 # Configure hostname and ports for services