CI: try to fix gh-pages

.github/workflows/gh-pages.yml

@@ -3,21 +3,15 @@ name: github pages
 on:
   push:
     branches:
-      - master  # Set a branch name to trigger deployment
+      - main
 
 jobs:
   deploy:
     runs-on: ubuntu-latest
+    permissions:
+      contents: write
     steps:
       - uses: actions/checkout@main
-
-      - name: Cache opam
-        id: cache-opam
-        uses: actions/cache@v2
-        with:
-          path: ~/.opam
-          key: opam-ubuntu-latest-4.12.0
-
       - uses: ocaml/setup-ocaml@v3
         with:
           ocaml-compiler: '5.03'
@@ -39,5 +33,5 @@ jobs:
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./_build/default/_doc/_html/
-          destination_dir: dev
-          enable_jekyll: true
+          destination_dir: .
+          enable_jekyll: false