Use new queue rules for mergify bot (#2301)

* Use new queue rules

* Add queue action

* Remove method from the queue rule

* Correct yaml

* Comment about empty conditions

Author: jneira

.github/mergify.yml

@@ -1,9 +1,15 @@
+queue_rules:
+  - name: default
+    # Mergify always respects the branch protection settings
+    # so we can left empty mergify own ones
+    conditions: []
+
 pull_request_rules:
-  - actions:
-      merge:
-        strict: smart+fasttrack
-        method: squash
-    name: Automatically merge pull requests
+  - name: Automatically merge pull requests
     conditions:
       - label=merge me
       - '#approved-reviews-by>=1'
+    actions:
+      queue:
+        method: squash
+        name: default