chore: Update ZooKeeper to 3.9.3 pre-25.3.0 (#836)

* chore: Update ZooKeeper to 3.9.3 in getting_started script

* test: Update ZooKeeper to 3.9.3 in test definitions

Author: Techassi

docs/modules/kafka/examples/getting_started/zookeeper.yaml

@@ -5,7 +5,7 @@ metadata:
   name: simple-zk
 spec:
   image:
-    productVersion: 3.9.2
+    productVersion: 3.9.3
   servers:
     roleGroups:
       default:

tests/test-definition.yaml

@@ -22,9 +22,10 @@ dimensions:
   - name: zookeeper
     values:
       - 3.9.2
+      - 3.9.3
   - name: zookeeper-latest
     values:
-      - 3.9.2
+      - 3.9.3
   - name: upgrade_old
     values:
       - 3.7.1