(maint) fix workflow

Author: mkevenaar

.github/workflows/toc.yaml

@@ -9,6 +9,12 @@
   jobs:
     build:
       runs-on: ubuntu-latest
+
+      permissions:
+        # Give the default GITHUB_TOKEN write permission.
+        # https://github.blog/changelog/2023-02-02-github-actions-updating-the-default-github_token-permissions-to-read-only/
+        contents: write
+
       timeout-minutes: 5
       steps:
         - uses: actions/[email protected]