Description of problem:

In Hammer CLI, when we create external user-group, the only input parameter
available is --auth-source-id. No option available with --auth-source-name as a parameter.

#hammer user-group external create --help
Usage:
hammer user-group external create [OPTIONS]

Options:
--auth-source-id AUTH_SOURCE_ID ID of linked authentication source
--name NAME External user group name
--user-group USER_GROUP_NAME Name to search by
--user-group-id USER_GROUP_ID
-h, --help print help

Version-Release number of selected component (if applicable):

1. rpm -qa|grep -i satellite
   satellite-6.2.6-2.0.el7sat.noarch
2. hammer --version
   hammer (0.5.1.11)

How reproducible:

1. hammer auth-source ldap list
   --|--------|------|----|--------------
   ID | NAME | LDAPS? | PORT | SERVER TYPE
   --|--------|------|----|--------------
   3 | AD-AUTH | | 389 | AuthSourceLdap
   5 | IPA-AUTH | | 389 | AuthSourceLdap
   7 | rhel-idm | | 389 | AuthSourceLdap
   --|--------|------|----|--------------

1. hammer user-group list
   --|--------
   ID | NAME
   --|--------
   4 | onlyview
   --|--------

1. hammer user-group external list --user-group onlyview
   --|-----------|-----------
   ID | NAME | AUTH SOURCE
   --|-----------|-----------
   2 | view-access | rhel-idm
   --|-----------|-----------

1. hammer user-group external create --auth-source-id 7 --name view-access-1 --user-group onlyview
   External user group created

1. hammer user-group external list --user-group onlyview
   --|-------------|-----------
   ID | NAME | AUTH SOURCE
   --|-------------|-----------
   2 | view-access | rhel-idm
   3 | view-access-1 | rhel-idm
   --|-------------|-----------

1. hammer user-group external create --help
   Options:
   --auth-source-id AUTH_SOURCE_ID ID of linked authentication source
   --name NAME External user group name
   --user-group USER_GROUP_NAME Name to search by
   --user-group-id USER_GROUP_ID
   -h, --help print help

From the above we can see there is only one option to create external user-group i.e. --auth-source-id.

No option available with --auth-source-name or --auth-source as a input parameter.

Expected results:
auth-source-name or auth-source must be available as a input parameter.

Additional info:
This makes scripting the creation of external user-groups difficult as you must first parse the auth source list to find the id.