attempt with bash var

Signed-off-by: Charalampos Mainas <charalampos.mainas@gmail.com>

Author: cmainas

.github/workflows/build_and_manifest.yml

@@ -28,7 +28,8 @@ jobs:
         echo "${{ toJSON(fromJSON(inputs.changed)['hello-world'].unikraft) }}"
         echo "${{ toJSON(fromJSON(inputs.changed).hello-world.unikraft) }}"
         echo "${{ toJSON(fromJSON(inputs.changed).hello-world.unikraft.firecracker) }}"
-        echo "${{ join(fromJSON(inputs.changed).hello-world.unikraft.${{ inputs.monitor }}, ' '), amd64 }}"
+        MON=${{inputs.monitor}}
+        echo "${{ join(fromJSON(inputs.changed).hello-world.unikraft.$MON, ' '), amd64 }}"
 
   build-image-amd64:
     name: Build and push image