fixup

Author: shmokmt

script.sh

@@ -55,7 +55,8 @@ for docker_file in "${docker_files[@]}" ; do
     echo "::group:: result of build --check"
     echo "$check_result"
     echo "::endgroups::"
-    if [[ -z "$(echo "$check_result" | jq '.warnings // empty')" ]]; then
+    warnings=$(echo "$check_result" | jq '.warnings')
+    if [[ "$warnings" == "null" ]]; then
         echo "No warnings found in ${docker_file}"
         continue
     fi