chore: Add GitHub App

Author: wasabeef

.github/workflows/release.yml

@@ -102,6 +102,15 @@ jobs:
         with:
           name: sha256
 
+      # GitHub Apps
+      - name: Generate github apps token
+        id: app-token
+        uses: actions/create-github-app-token@v1
+        with:
+          app-id: ${{ secrets.FLUTTEGEN_APP_ID }}
+          private-key: ${{ secrets.FLUTTEGEN_APP_PRIVATE_KEY }}
+          owner: ${{ github.repository_owner }}
+
       - id: version
         run: echo "::set-output name=version::${GITHUB_REF##*/}"
 
@@ -112,7 +121,7 @@ jobs:
           echo ::set-output name=sha256_macos::$(cat fluttergen-macos.sha256 | awk '{ print $1 }')
       - uses: peter-evans/repository-dispatch@v3
         with:
-          token: ${{ secrets.PAT_FLUTTERGEN }}
+          token: ${{ steps.app-token.outputs.token }}
           repository: FlutterGen/homebrew-tap
           event-type: update-tap
           client-payload: '{ "sha256_linux": "${{ steps.checksum.outputs.sha256_linux }}", "sha256_macos": "${{ steps.checksum.outputs.sha256_macos }}", "version": "${{ steps.version.outputs.version }}" }'