fixing fatal: couldn't find remote ref 484/merge error

.github/workflows/pdm-lock-automation.yaml

@@ -76,10 +76,10 @@ jobs:
             echo "Nothing to commit"
           else
             echo "Changes detected in compared to the SELF branch."
+            git fetch origin ${{ github.ref_name }}
             git add pdm.lock
             pip install pre-commit~=3.6.2
             pre-commit run pdm-lock-check
-            git fetch origin ${{ github.ref_name }}
             git commit -m "Update pdm.lock for ${{ matrix.directory }}"
             git pull origin ${{ github.ref_name }} --no-rebase
             git push origin ${{ github.ref_name }}