use specific branch

Author: linev

.github/workflows/jsroot-ci-79.yml

@@ -72,6 +72,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: 'linev/jsroot-test'
+          ref: '7.9'
           path: 'jsroot-test'
 
       - name: Show jsroot status