fix name

Author: bakkot

.github/workflows/pr-preview.yml

@@ -94,7 +94,7 @@ jobs:
           node-version: lts/*
           use-npm-ci: true
       - run: npm run build-only
-      - run: node scripts/insert_snapshot_warning
+      - run: node scripts/insert-snapshot-warning.js
       - run: ./scripts/deploy-github-pages.sh --pr ${{ github.event.number }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}