CLI autocompletion can't handle empty {}

Description of problem:
CLI autocompletion can't handle empty {}

Steps to Reproduce:

1. embed-server
2. /subsystem=elytron/token-realm=JwtRealm:add(jwt={}<TAB><TAB><TAB><TAB><TAB>

Actual results:
/subsystem=elytron/token-realm=JwtRealm:add(jwt={}}}}}}

Expected results:
/subsystem=elytron/token-realm=JwtRealm:add(jwt={}