Also update AS400 doc version from 21.0.0 to 21.0.6

Author: nadment

docs/hop-user-manual/modules/ROOT/pages/database/databases/as400.adoc

@@ -25,7 +25,7 @@ under the License.
 | Option | Info
 |Type | Relational
 |Driver | Included
-|Version Included | 21.0.0
+|Version Included | 21.0.6
 |Hop Dependencies | None
 |Documentation | https://www.ibm.com/support/knowledgecenter/ssw_ibm_i_71/rzahh/javadoc/com/ibm/as400/access/doc-files/JDBCProperties.html[Documentation Link]
 |JDBC Url | jdbc:as400://hostname/default-schema