mergify: release review required stage

Author: 0xc0170

.mergify.yml

@@ -155,3 +155,16 @@ pull_request_rules:
         add:
           - do not merge
 
+  # Check if version label is applied
+  - name: release version is a must for merged PRs
+    conditions:
+      - merged
+      - -label~=^(release-version)
+    actions:
+      label:
+        add:
+          - Release review required
+      comment:
+        message: This PR does not contain release version label after merging.
+
+