fix: docker/Dockerfile.python-3.6 to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-DEBIAN11-GLIBC-5927133
- https://snyk.io/vuln/SNYK-DEBIAN11-GLIBC-5927133
- https://snyk.io/vuln/SNYK-DEBIAN11-DPKG-2847942
- https://snyk.io/vuln/SNYK-DEBIAN11-EXPAT-7855504
- https://snyk.io/vuln/SNYK-DEBIAN11-LIBTASN16-3061097

docker/Dockerfile.python-3.6

@@ -1,4 +1,4 @@
-FROM python:3.6-slim
+FROM python:3.14.0a1-slim
 
 MAINTAINER Snyk Ltd