Drop --layers from the build to avoid slow layer commits, and default

PULL_POLICY to missing so the base image is only re-pulled when absent.

build.sh

@@ -3,8 +3,7 @@ set -euo pipefail
 
 IMAGE_NAME="tintounn/my-fedora"
 IMAGE_TAG="latest"
-PULL_POLICY="${PULL_POLICY:-always}"
+PULL_POLICY="${PULL_POLICY:-missing}"
 
 echo "[INFO] Build de l'image (pull=${PULL_POLICY})..."
-buildah bud --layers --pull="${PULL_POLICY}" --isolation chroot -t localhost/${IMAGE_NAME}:${IMAGE_TAG} .
-
+buildah bud --pull="${PULL_POLICY}" --isolation chroot -t localhost/${IMAGE_NAME}:${IMAGE_TAG} .