Update rfc-action.yml (#39)

Author: rzadp

.github/workflows/rfc-action.yml

@@ -12,6 +12,12 @@ jobs:
     if: ${{ github.event.issue.pull_request && startsWith(github.event.comment.body, '/rfc') }}
     runs-on: ubuntu-latest
     steps:
+      - name: Generate a token
+        id: generate_token
+        uses: actions/create-github-app-token@v1
+        with:
+          app_id: ${{ secrets.RFC_BOT_APP_ID }}
+          private_key: ${{ secrets.RFC_BOT_PRIVATE_KEY }}
       - uses: paritytech/rfc-action@c8b00e2264712a7093a5b64c6ffd2298b49d41cf # v0.0.4
-    env:
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        env:
+          GH_TOKEN: ${{ steps.generate_token.outputs.token }}