fix(update): don't output locked message when updating images

apps/update-sources/src/docker.ts

@@ -11,7 +11,7 @@ const updateImages = (imagePath: string): string | undefined => {
 
     const out = spawnSync('updateImages', [imagePath], { shell: true }).stdout.toString();
 
-    if (!out.startsWith('# Locked')) {
+    if (out.length > 1) {
         return out;
     }
 };

modules/docker/updateImage.nix

@@ -21,7 +21,7 @@ writeShellApplication {
 
         output="$IMAGE $TAG"
 
-        if ! grep "Locked" "$FILE"; then
+        if ! grep "Locked" "$FILE" &> /dev/null; then
             if [[ "$CURRENT_DIGEST" != "$NEW_DIGEST" ]]; then
                 echo -e "• $output:\n   $CURRENT_DIGEST\n → $NEW_DIGEST\n"
                 PREFETCH=$(nix-prefetch-docker "$IMAGE" "$TAG")