infra: Use same image in tests as on prod (#74)

Also stop installing git, which we no longer use.

.circleci/config.yml

@@ -6,17 +6,12 @@ orbs:
 jobs:
   run-tests:
     docker:
-      - image: pandoc/core:latest-ubuntu
-    environment:
-      # Set DEBIAN_FRONTEND to avoid tzdata interactive input
-      # https://techoverflow.net/2019/05/18/how-to-fix-configuring-tzdata-interactive-input-when-building-docker-images/
-      DEBIAN_FRONTEND: noninteractive
+      # Use the same image as the base of the Dockerfile
+      - image: python:3.13-slim
     steps:
       - checkout
-      - run: apt-get update && apt-get install -y python3-venv pip
+      - run: apt-get update && apt-get install -y pandoc
       - run: |
-          python3 -m venv venv
-          source venv/bin/activate
           pip install -r requirements.txt
           pip install pytest
           pytest

Dockerfile

@@ -1,6 +1,7 @@
-FROM python:3.13-slim-bullseye
+# When updating the image, remember to make the same update in the CircleCI config
+FROM python:3.13-slim
 
-RUN apt-get update && apt-get install git pandoc -y
+RUN apt-get update && apt-get install pandoc -y
 
 COPY requirements.txt /requirements.txt
 RUN pip install -r /requirements.txt