ci: add token for cron-update-rust.yml

.github/workflows/cron-update-rust.yml

@@ -10,6 +10,11 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
+      - uses: tibdex/github-app-token@v1
+        id: generate-token
+        with:
+          app_id: ${{ secrets.APP_ID }}
+          private_key: ${{ secrets.APP_PRIVATE_KEY }}
       - name: Update rust-version to use latest stable
         run: |
           set -x
@@ -30,7 +35,7 @@ jobs:
         if: env.changes_made == 'true'
         uses: peter-evans/create-pull-request@v6
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
+          token: ${{ steps.generate-token.outputs.token }}
           author: Update Rustc Bot <bot@example.com>
           committer: Update Rustc Bot <bot@example.com>
           branch: create-pull-request/update-rust-version