GH-3226: Redis Stream Outbound Channel Adapter

Fixes https://github.com/spring-projects/spring-integration/issues/3226

* Redis stream message handler support.
* This is the outbound part publishing message to the actual stream using ReactiveStreamOperations

* Addition of more test cases with one using `MessageChannel`.

* Improvements after PR review.

* Removed failed test reading List from a Stream
* Code style clean up
* Remove `rawtypes` usage
* Remove redundant inner classes for test model
* Add `What's New` note

src/reference/asciidoc/redis.adoc

@@ -788,3 +788,8 @@ However, the resources protected by such a lock may have been compromised, so su
 You should set the expiry at a large enough value to prevent this condition, but set it low enough that the lock can be recovered after a server failure in a reasonable amount of time.
 
 Starting with version 5.0, the `RedisLockRegistry` implements `ExpirableLockRegistry`, which removes locks last acquired more than `age` ago and that are not currently locked.
+
+[[redis-stream-outbound]]
+=== Redis Stream Outbound Channel Adapter
+
+TBD

src/reference/asciidoc/whats-new.adoc

@@ -23,7 +23,12 @@ See <<./kafka.adoc#kafka,Spring for Apache Kafka Support>> for more information.
 ==== R2DBC Channel Adapters
 
 The Channel Adapters for R2DBC database interaction have been introduced.
-See <<./r2dbc.adoc#r2dbc,R2DBC Support>>  for more information.
+See <<./r2dbc.adoc#r2dbc,R2DBC Support>> for more information.
+
+==== Redis Stream Support
+
+The Channel Adapters for Redis Stream support have been introduced.
+See <<./redis.adoc#redis-stream-outbound,Redis Stream Outbound Channel Adapter>> for more information.
 
 [[x5.4-general]]
 === General Changes