Add --break-system-packages so pip works on system Python

core/Dockerfile

@@ -13,8 +13,8 @@ RUN --mount=type=cache,target=/root/.cache \
   # Mailman html to plaintext conversion uses lynx.
   # psutil needs linux-headers to compile on musl c library.
     && apk add --no-cache bash su-exec postgresql-client mysql-client curl python3 py3-pip linux-headers py-cryptography mariadb-connector-c lynx tzdata \
-    && python3 -m pip install -U pip setuptools wheel \
-        && python3 -m pip install psycopg2 \
+    && python3 -m pip install --break-system-packages -U pip setuptools wheel \
+        && python3 -m pip install --break-system-packages psycopg2 \
                    gunicorn==19.9.0 \
                    pymysql \
                    -r /tmp/requirements.txt \