Fix issue

Signed-off-by: ZePan110 <ze.pan@intel.com>

Author: ZePan110

.github/workflows/manual-image-build.yml

@@ -51,7 +51,7 @@ jobs:
 
   image-build:
     needs: get-test-matrix
-    if: ${{ fromJSON(needs.get-test-matrix.outputs.nodes).length != 0 }}
+    if: ${{ needs.get-test-matrix.outputs.nodes != '' }}
     strategy:
       matrix:
         node: ${{ fromJson(needs.get-test-matrix.outputs.nodes) }}