update to min python version for current dependency set

Author: ihalatci

circleci/images/citusupgradetester/Dockerfile

@@ -1,5 +1,5 @@
 # we cannot easily upgrade to python 3.11 as our mitmproxy fork does not ship with it
-FROM python:3.9.7-slim-bullseye AS base
+FROM python:3.10-slim-bullseye AS base
 
 # add unpriviliged user for tests
 RUN useradd -ms /bin/bash circleci

circleci/images/failtester/Dockerfile

@@ -1,5 +1,5 @@
 # we cannot easily upgrade to python 3.11 as our mitmproxy fork does not ship with it
-FROM python:3.9.7-slim-bullseye
+FROM python:3.10-slim-bullseye
 
 # add unpriviliged user for tests
 RUN useradd -ms /bin/bash circleci

circleci/images/pgupgradetester/Dockerfile

@@ -1,5 +1,5 @@
 # we cannot easily upgrade to python 3.11 as our mitmproxy fork does not ship with it
-FROM python:3.9.7-slim-bullseye
+FROM python:3.10-slim-bullseye
 
 # add unpriviliged user for tests
 RUN useradd -ms /bin/bash circleci