chore: checkout dev branch in ci

fixes #348

Author: bennypowers

Diff for: .github/workflows/pages.yml

@@ -22,6 +22,10 @@ jobs:
     runs-on: ubuntu-latest
     name: Build site and deploy to GHPages
     steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+          ref: dev
       - name: Install node 16
         uses: actions/setup-node@v3
         with: