nmcli: Add 'slave-type bridge' to nmcli command if type is bridge-slave (#2409) (#2422)

(cherry picked from commit b5f8ae4320)

Co-authored-by: spike77453 <spike77453@users.noreply.github.com>

plugins/modules/net_tools/nmcli.py

@@ -752,6 +752,7 @@ class Nmcli(object):
             })
         elif self.type == 'bridge-slave':
             options.update({
+                'connection.slave-type': 'bridge',
                 'bridge-port.path-cost': self.path_cost,
                 'bridge-port.hairpin-mode': self.hairpin,
                 'bridge-port.priority': self.slavepriority,