ci(mergify): upgrade configuration to current format

Author: mergify[bot]

.mergify.yml

@@ -1,29 +1,28 @@
 queue_rules:
+  - name: duplicated main from rebase updates then merge to master
+    queue_conditions:
+      - label=automerge:merge
+      - label=automerge:rebase
+    merge_conditions: []
+    merge_method: merge
+    update_method: rebase
+  - name: duplicated main from squash to master
+    queue_conditions:
+      - label=automerge:merge
+      - label=automerge:squash
+    merge_conditions: []
+    merge_method: squash
   - name: main
-    conditions:
+    queue_conditions:
+      - label=automerge:merge
+    merge_conditions:
       - base=main
       # Require integration tests before merging only
       - check-success=Cloudflare Pages
+    merge_method: merge
+
 pull_request_rules:
-  - name: merge to master
-    conditions:
-      - label=automerge:merge
-    actions:
-      queue:
-        name: main
-        method: merge
-  - name: rebase updates then merge to master
-    conditions:
-      - label=automerge:rebase
-    actions:
-      queue:
-        name: main
-        method: merge
-        update_method: rebase
-  - name: squash to master
-    conditions:
-      - label=automerge:squash
+  - name: merge to master + rebase updates then merge to master + squash to master
+    conditions: []
     actions:
       queue:
-        name: main
-        method: squash