Migrate to ruby-go-gem's app

Author: sue445

.github/workflows/rbs-collection-updater.yml

@@ -22,8 +22,8 @@ jobs:
       - uses: actions/create-github-app-token@v1
         id: app-token
         with:
-          app-id: ${{ secrets.GH_APP_ID }}
-          private-key: ${{ secrets.GH_APP_PRIVATE_KEY }}
+          app-id: ${{ secrets.RUBY_GO_GEM_BOT_APP_ID }}
+          private-key: ${{ secrets.RUBY_GO_GEM_BOT_PRIVATE_KEY }}
 
       - uses: peter-evans/create-pull-request@v7
         with: