use updated final state hardron test ref file

Author: latessa

.github/workflows/test-events-Pythia-Isr-Hadron.yaml

@@ -55,7 +55,7 @@ jobs:
       uses: actions/checkout@v4
       with:
         repository: JETSCAPE/TEST-EXAMPLES
-        ref: main
+        ref: Passing-QCDStringList-to-MUSIC
         path: TEST-EXAMPLES
 
     - name: Run Pythia ISR Hadron File Tests