try this

Author: Rich-Harris

.github/workflows/docs-preview-create.yml

@@ -22,7 +22,7 @@ jobs:
       - run: pnpm install --frozen-lockfile
 
       - name: Checkout
-        run: git switch -c ${{ env.BRANCH }} || git switch ${{ env.BRANCH }}
+        run: git fetch origin ${{ env.BRANCH }} && git checkout ${{ env.BRANCH }} || git checkout -b ${{ env.BRANCH }}
 
       - name: Sync
         run: cd apps/svelte.dev && pnpm sync-docs --owner="${{ github.event.client_payload.owner }}" -p "${{ github.event.client_payload.package }}#${{ github.event.client_payload.branch }}"