drop mergify and replace with bors

.github/workflows/update-flake-lock.yml

@@ -0,0 +1,25 @@
+name: update-flake-lock
+on:
+  workflow_dispatch: # allows manual triggering
+  schedule:
+    - cron: '0 0 * * 1,4' # Run twice a week
+
+jobs:
+  lockfile:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+      - name: Install Nix
+        uses: cachix/install-nix-action@v19
+        with:
+          github_access_token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Update flake.lock
+        uses: DeterminateSystems/update-flake-lock@v16
+        with:
+          pr-body: |
+            Automated changes by the update-flake-lock
+            ```
+            {{ env.GIT_COMMIT_MESSAGE }}
+            ```
+            bors merge

.github/workflows/upgrade-flakes.yml

@@ -1,22 +0,0 @@
-name: "Update flakes"
-on:
-  repository_dispatch:
-  workflow_dispatch:
-  # monthly updates
-  schedule:
-    - cron:  '0 10 1 * 0'
-jobs:
-  createPullRequest:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - name: Install Nix
-        uses: cachix/install-nix-action@v19
-        with:
-          extra_nix_config: |
-            experimental-features = nix-command flakes
-            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
-      - name: Update flake.lock
-        uses: DeterminateSystems/update-flake-lock@v16
-        with:
-          token: ${{ secrets.GH_TOKEN_FOR_UPDATES }}

.mergify.yml

@@ -1,9 +0,0 @@
-pull_request_rules:
-  - name: automatic merge on CI success
-    conditions:
-      - check-success=tests (ubuntu-latest)
-      - author=nix-direnv-bot
-    actions:
-      merge:
-        method: merge
-      delete_head_branch: {}