Add token permissions to release workflow. (pypa#192)

Required for trusted publishing.

Author: di

.github/workflows/release.yml

@@ -11,6 +11,9 @@ on:
 jobs:
   build-and-publish:
     runs-on: ubuntu-latest
+    permissions:
+      # IMPORTANT: this permission is mandatory for trusted publishing
+      id-token: write
     steps:
     - name: Checkout
       uses: actions/checkout@v3