fix: Dockerfile to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-ALPINE320-EXPAT-7908298
- https://snyk.io/vuln/SNYK-ALPINE320-EXPAT-7908299
- https://snyk.io/vuln/SNYK-ALPINE320-EXPAT-7908300

Dockerfile

@@ -1,5 +1,5 @@
 # API Dockerfile
-FROM python:3.9-alpine
+FROM python:3.12.0a1-alpine
 
 # Copy requirements file
 COPY requirements.txt .