add permission to use gh action token

Author: alistairewj

.github/workflows/test_bq_auth.yml

@@ -10,6 +10,9 @@ env:
 jobs:
   create-tables:
     runs-on: ubuntu-latest
+    permissions:
+        contents: 'read'
+        id-token: 'write'
     steps:
       - name: Check out repository code
         uses: actions/checkout@v3