Setup shared image stores

.forgejo/workflows/build.yaml

@@ -20,10 +20,16 @@ jobs:
             git \
             netavark \
           ;
+          shared=/var/lib/shared-containers
           sed /usr/share/containers/storage.conf \
             -e '/^#\?mount_program/c\
           mount_program = "/usr/bin/fuse-overlayfs"' \
+            -e "/^additionalimagestores/a"'\
+            '"\"$shared\"" \
           > /etc/containers/storage.conf
+          mkdir -p $shared/overlay-images $shared/overlay-layers
+          touch $shared/overlay-images/images.lock
+          touch $shared/overlay-layers/layers.lock
       -
         name: Checkout repository
         run: |