Part of OpenHistoricalMap/issues#786, adjusting workflow.

.github/workflows/ohm.upstream-sync.yml

@@ -28,7 +28,7 @@ jobs:
           git config --global user.email "[email protected]"
           git remote add upstream "${UPSTREAM}"
           git fetch upstream master
-          git branch -D the-sacrifice
+          git branch -D the-sacrifice &>/dev/null  
           git checkout -b the-sacrifice
       - name: Make our script executable
         run: chmod +x ./scripts/upstream_sync.sh