release oslo.messaging 10.2.4 for train

That release urgent fixes.
We need to stick to bugfix version even if feature are landed because ussuri
start with 10.3.0.

Change-Id: I1ab1770719499c84b046fff619686b8acb7b1288

deliverables/train/oslo.messaging.yaml

@@ -51,6 +51,10 @@ releases:
     projects:
       - repo: openstack/oslo.messaging
         hash: 56fc332608028ba4c671255e8bd9223a0bae762d
+  - version: 10.2.4
+    projects:
+      - repo: openstack/oslo.messaging
+        hash: 82281a0d4e6abffa93175f30b2cbd7acca3cf9fb
 branches:
   - name: stable/train
     location: 10.2.0