document scala suppress API
Document the minor API change.
Reviewers: Casey Green Guozhang Wang  Bill Bejeck
</p>
<h3><a id="streams_api_changes_230" href="#streams_api_changes_230">Streams API changes in 2.3.0</a></h3>
+ <p>Version 2.3.0 adds the Suppress operator to the <code>kafka-streams-scala</code> Ktable API.</p>
<p>
As of 2.3.0 Streams now offers an in-memory version of the window store, in addition to the persistent one based on RocksDB. The new public interface <code>inMemoryWindowStore()</code> is added to Stores that provides a built-in in-memory window store.
</p>
