ci(mergify): upgrade configuration to current format (#10956)

* ci(mergify): upgrade configuration to current format

* patch up auto-upgrade brokenness

yet again

---------

Co-authored-by: Mergify <37929162+mergify[bot]@users.noreply.github.com>
Co-authored-by: brandon s allbery kf8nh <allbery.b@gmail.com>

Author: mergify[bot]

.github/mergify.yml

@@ -8,23 +8,23 @@ priority_rules:
       - 'label=priority: high :fire:'
     priority: 3000
 
-  # The idea is we slightly prioritize those PRs because we're in
-  # a release cycle if a PR matches.
-  - name: release branch
-    conditions:
-      - 'base~=^3\.'
-      - 'label!=backport'
-    priority: 2700
-
   - name: priority for queue `default`
     conditions:
       - queue-name=default
-    priority: 2500
+    priority: 2750
 
   - name: priority for queue `squash-merge`
     conditions:
       - queue-name=squash-merge
-    priority: 2500
+    priority: 2750
+
+  # The idea is we slightly prioritize those PRs because we're in
+  # a release cycle if a PR matches.
+  - name: release branch
+    conditions:
+      - 'base~=^3\.'
+      - 'label!=backport'
+    priority: 2800
 
 pull_request_rules: