Add unregistering Kafka nodes to known KRaft limitations (strimzi#10313)

Signed-off-by: Jakub Scholz <www@scholzj.com>

documentation/assemblies/deploying/assembly-kraft-mode.adoc

@@ -57,6 +57,7 @@ Currently, the KRaft mode in Strimzi has the following major limitations:
 It is considered early-access in Apache Kafka 3.7.x.
 (Storage with `type: jbod` configuration can be used also with older Kafka versions, but the JBOD array can contain only one disk.)
 * Scaling of KRaft controller nodes up or down is not supported.
+* Unregistering Kafka nodes removed from the Kafka cluster.
 
 NOTE: If you are using JBOD storage, you can xref:ref-jbod-storage-str[change the volume that stores the metadata log].