feat: use bot account to create PR

This might run CI?

.forgejo/workflows/update-flake.yaml

@@ -1,4 +1,5 @@
 on:
+  push:
   schedule:
     - cron: '0 0 * * 1'
 
@@ -27,7 +28,7 @@ jobs:
           curl -X POST "${{ env.GITHUB_API_URL }}/repos/${{ env.GITHUB_REPOSITORY }}/pulls"
           --fail
           -H "Content-Type: application/json"
-          -H "Authorization: token ${{ env.GITHUB_TOKEN }}"
+          -H "Authorization: token ${{ secrets.BOT_TOKEN }}"
           -d '{
                "title": "build(flake): update inputs",
                "body": "",