Followup for HIVE-9013 : Hidden conf vars still visible through beeline

HIVE-9013 introduced the ability to hide certain conf variables when output through the "set" command. However, there still exists one further bug in it that causes these variables to still be visible through beeline connecting to HS2, wherein HS2 exposes hidden variables such as the HS2's metastore password when "set" is run.