mark 3.3.4/6 deprecated

Author: maltesander

docs/modules/hdfs/partials/supported-versions.adoc

@@ -4,5 +4,5 @@
 
 - 3.4.1 (LTS)
 - 3.4.0 (deprecated)
-- 3.3.6 - Please note that there is a https://github.com/stackabletech/hdfs-operator/issues/440[known issue] related to NameNode bootstrapping which can happen in rare cases.
-- 3.3.4
+- 3.3.6 (deprecated) - Please note that there is a https://github.com/stackabletech/hdfs-operator/issues/440[known issue] related to NameNode bootstrapping which can happen in rare cases.
+- 3.3.4 (deprecated)