ci(mergify): upgrade configuration to current format (#1924)

Co-authored-by: Mergify <37929162+mergify[bot]@users.noreply.github.com>

.github/mergify.yml

@@ -1,21 +1,21 @@
 queue_rules:
   - name: default
-    conditions:
+    queue_conditions:
       - check-success=all
       - label=automerge
       - base=main
       - "#changes-requested-reviews-by=0"
       - "#approved-reviews-by>=1"
-
-pull_request_rules:
-  - name: automatic merge when CI passes on main
-    conditions:
+    merge_conditions:
       - check-success=all
       - label=automerge
       - base=main
       - "#changes-requested-reviews-by=0"
       - "#approved-reviews-by>=1"
+    merge_method: merge
+
+pull_request_rules:
+  - name: automatic merge when CI passes on main
+    conditions: []
     actions:
       queue:
-        name: default
-        method: merge