ci: don't persist credentials to git config

Because we don't need to for this workflow and it conflicts with the use of a
custom PAT later

.github/workflows/update-version-refs.yml

@@ -15,6 +15,7 @@ jobs:
     - uses: actions/checkout@v3
       with:
         fetch-depth: 0
+        persist-credentials: false
 
     - name: Confirm update to released tag is allowed
       run: |