Fix variable name typo in the redis.adoc

Author: Mini256

src/reference/asciidoc/redis.adoc

@@ -785,9 +785,10 @@ public ReactiveRedisStreamMessageHandler reactiveValidatorMessageHandler(
         ReactiveRedisConnectionFactory reactiveRedisConnectionFactory) {
     ReactiveRedisStreamMessageHandler reactiveStreamMessageHandler =
         new ReactiveRedisStreamMessageHandler(reactiveRedisConnectionFactory, "myStreamKey"); <1>
-    reactiveRedisStreamMessageHandler.setSerializationContext(serializationContext); <2>
-    reactiveRedisStreamMessageHandler.setHashMapper(hashMapper); <3>
-    reactiveRedisStreamMessageHandler.setExtractPayload(true); <4>
+    reactiveStreamMessageHandler.setSerializationContext(serializationContext); <2>
+    reactiveStreamMessageHandler.setHashMapper(hashMapper); <3>
+    reactiveStreamMessageHandler.setExtractPayload(true); <4>
+    return reactiveStreamMessageHandler;
 }
 ----
 <1> Construct an instance of `ReactiveRedisStreamMessageHandler` using `ReactiveRedisConnectionFactory` and stream name to add records.
@@ -885,4 +886,4 @@ You should set the expiry at a large enough value to prevent this condition, but
 Starting with version 5.0, the `RedisLockRegistry` implements `ExpirableLockRegistry`, which removes locks last acquired more than `age` ago and that are not currently locked.
 
 String with version 5.5.6, the `RedisLockRegistry` is support automatically clean up cache for redisLocks in `RedisLockRegistry.locks` via `RedisLockRegistry.setCacheCapacity()`.
-See its JavaDocs for more information.
+See its JavaDocs for more information.