CI checkout fix

Author: MekDrop

.github/workflows/on-pull-request.yml

@@ -75,8 +75,6 @@ jobs:
     steps:
       - name: Checkouting code...
         uses: actions/checkout@v4
-        with:
-          ref: ${{ github.head_ref }}
 
       - name: Downloading build artifact....
         uses: actions/download-artifact@v4