Fix ldap user provider parent_id lookup (#319)

* fix get parent id lookup

* fix rubocop lint

lib/puppet/provider/keycloak_ldap_user_provider/kcadm.rb

@@ -58,19 +58,15 @@ def self.prefetch(resources)
   end
 
   def get_parent_id(realm)
-    parent_id = nil
-    output = kcadm('get', 'realms', realm, nil, ['id'])
+    output = kcadm('get', "realms/#{realm}", nil, nil, ['id'])
     Puppet.debug("#{realm} realms: #{output}")
     begin
       data = JSON.parse(output)
     rescue JSON::ParserError
-      Puppet.debug('Unable to parse output from kcadm get realms')
-      data = []
-    end
-    data.each do |d|
-      parent_id = d['id']
+      Puppet.debug("Unable to parse output from kcadm get realms/#{realm}")
+      data = {}
     end
-    parent_id
+    data['id']
   end
 
   def create