Sign fixture sync commits via GitHub API

.github/workflows/sync-test-fixtures.yml

@@ -12,46 +12,24 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v6
       - name: Sync fixtures
+        id: sync
         run: |
           TMP_DIR=$(mktemp -d)
           curl -fsSL "https://codeload.github.com/dnsimple/dnsimple-developer/tar.gz/refs/heads/main" \
             | tar -xz -C "$TMP_DIR"
           rsync -a --delete "$TMP_DIR/dnsimple-developer-main/fixtures/v2/api/" src/test/resources/com/dnsimple/
-      - name: Create a PR to sync fixtures if there are changes
-        run: |
-          cat <<'MD' > pr_body.md
-          This PR replaces the fixtures in this repository with those from https://github.com/dnsimple/dnsimple-developer/
-
-          ## Checklist
-          - [ ] Close and re-open this PR to trigger the CI workflow (it does not run automatically)
-          - [ ] Ensure the CI workflow passes before merging
-          MD
-
-          # Configure Git identity for the workflow
-          git config --global user.name "github-actions"
-          git config --global user.email "github-actions@github.com"
-
-          # Create and switch to a new branch
-          BRANCH="chore/sync-fixtures-${GITHUB_RUN_ID}"
-          NOW="$(date +'%Y-%m-%d %H:%M:%S')"
-          git checkout -b "$BRANCH"
-
-          # Stage changes
-          git add src/test/resources/com/dnsimple
-
-          # Commit if there are staged changes
-          if ! git diff --cached --quiet; then
-            git commit -m "chore: sync test fixtures as of $NOW"
-            git push -u origin "$BRANCH"
-
-            gh pr create \
-              --title "chore: Sync fixtures as of $NOW" \
-              --body-file pr_body.md \
-              --base main \
-              --head "$BRANCH" \
-              --label "task"
-          else
-            echo "No fixture changes detected; nothing to do"
-          fi
-        env:
-          GITHUB_TOKEN: ${{ github.token }}
+          echo "now=$(date +'%Y-%m-%d %H:%M:%S')" >> "$GITHUB_OUTPUT"
+      - name: Create PR with synced fixtures
+        uses: peter-evans/create-pull-request@v7
+        with:
+          sign-commits: true
+          add-paths: src/test/resources/com/dnsimple
+          commit-message: "chore: sync test fixtures as of ${{ steps.sync.outputs.now }}"
+          branch: "chore/sync-fixtures-${{ github.run_id }}"
+          title: "chore: Sync fixtures as of ${{ steps.sync.outputs.now }}"
+          body: |
+            This PR replaces the fixtures in this repository with those from https://github.com/dnsimple/dnsimple-developer/
+
+            ## Checklist
+            - [ ] Close and re-open this PR to trigger the CI workflow (it does not run automatically)
+            - [ ] Ensure the CI workflow passes before merging