Merge bitcoin/bitcoin#27777: ci: Prune dangling images on RESTART_CI_DOCKER_BEFORE_RUN

fa123077bc ci: Use podman for persistent workers (MarcoFalke)
fa9c65a74c ci: Prune dangling images on RESTART_CI_DOCKER_BEFORE_RUN (MarcoFalke)

Pull request description:

  This should prevent the persistent workers from running out of disk space. Containers are already removed, but not images. This is required since CI images are built and cached.

ACKs for top commit:
  hebasto:
    ACK fa123077bc

Tree-SHA512: 07c4faec57d659d1762e4e6d776c882ee48d4bac6ce6d438d56d9ab13277be3e39d6aa38816165a5a3e0938ac5d47674ee2921b6e115a4bb54e3e4910b34c4b6

ci/test/04_install.sh

@@ -42,7 +42,9 @@ if [ -z "$DANGER_RUN_CI_ON_HOST" ]; then
 
   if [ -n "${RESTART_CI_DOCKER_BEFORE_RUN}" ] ; then
     echo "Restart docker before run to stop and clear all containers started with --rm"
-    systemctl restart docker
+    podman container kill --all  # Similar to "systemctl restart docker"
+    echo "Prune all dangling images"
+    docker image prune --force
   fi
 
   # shellcheck disable=SC2086