Part of OpenHistoricalMap/issues#786, adjusting workflow.

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

@@ -15,10 +15,15 @@ jobs:
       run:
         shell: bash
     steps:
+      - name: Create sacrificial branch
+        uses: peterjgrainger/[email protected]
+        with:
+          branch: 'the-sacrifice'
       - name: Check out our repository
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
+          ref: 'the-sacrifice'
       - name: Check out the upstream repository
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

scripts/upstream_sync.sh

@@ -3,9 +3,6 @@
 # As we enter this script we have created `the-sacrifice` from our `main` branch and
 # have `git fetch`ed upstream/master.
 
-git branch -D the-sacrifice &>/dev/null
-git checkout -b the-sacrifice
-
 if [ ! -d "upstream" ]; then
   mkdir upstream
 fi