ci: use GitHub App token for prerelease workflow (#1369)

Author: Hweinstock

.github/workflows/prerelease-tarball.yml

@@ -29,9 +29,15 @@ jobs:
         run: |
           TARBALL_NAME=$(ls *.tgz | head -1 | xargs basename)
           echo "name=$TARBALL_NAME" >> $GITHUB_OUTPUT
+      - name: Generate GitHub App Token
+        id: app-token
+        uses: actions/create-github-app-token@v1
+        with:
+          app-id: ${{ vars.APP_ID }}
+          private-key: ${{ secrets.APP_PRIVATE_KEY }}
       - name: Create or update prerelease
         env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GH_TOKEN: ${{ steps.app-token.outputs.token }}
           TARBALL_NAME: ${{ steps.tarball.outputs.name }}
         run: |
           TAG="prerelease"