ci: update flake file automatically

.github/workflows/flake.yml

@@ -8,49 +8,38 @@ name: flake
 
 permissions:
   contents: write
-  pull-requests: write
 
 jobs:
   flake:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Generate token
-        id: token
-        uses: tibdex/github-app-token@v2
-        with:
-          app_id: ${{ secrets.TOKEN_EXCHANGE_APP }}
-          installation_retrieval_mode: id
-          installation_retrieval_payload: ${{ secrets.TOKEN_EXCHANGE_INSTALL }}
-          private_key: ${{ secrets.TOKEN_EXCHANGE_KEY }}
-          permissions: >-
-            {"contents": "write", "pull_requests": "write"}
-
       - name: Checkout source
         id: source
         uses: actions/checkout@v4
+        with:
+          token: ${{ secrets.BOT_ACCESS_TOKEN }}
 
       - name: Install nix
         id: nix
         uses: cachix/install-nix-action@v30
 
       - name: Update flake
         id: flake
-        uses: DeterminateSystems/update-flake-lock@v24
+        run: nix flake update
+
+      - name: Source rebase
+        id: rebase
+        run: git pull --autostash --rebase
+
+      - name: Commit changes
+        uses: EndBug/add-and-commit@v9
         with:
-          commit-msg: "chore(flake): updated lockfile"
-          pr-title: "chore: automated flake update"
-          pr-body: "New flakelock generated, automerge should handle that!"
-          pr-labels: renovate
-          git-author-name: GitHub Actions
-          git-author-email: [email protected]
-          token: ${{ steps.token.outputs.token }}
-
-      - name: Enable automerge
-        id: automerge
-        if: steps.flake.outputs.pull-request-operation == 'created'
-        run: gh pr merge --rebase --auto "${{ steps.flake.outputs.pull-request-number }}"
-        env:
-          GH_TOKEN: ${{ steps.token.outputs.token }}
+          author_name: GitHub Actions
+          author_email: [email protected]
+          add: flake.lock
+          message: "chore(flake): updated lockfile [skip ci]"
+          push: true
+          commit: --signoff
 
 ...