Update gh-pages.yml (AtsushiSakai#889)

Author: AtsushiSakai

.github/workflows/gh-pages.yml

@@ -6,6 +6,8 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
+    permissions:
+      id-token: write
     steps:
     - name: Setup python
       uses: actions/setup-python@v4