manager: fix assertion failure in active_connection_find()
Active-connections in the async_op_lst are not guaranteed to have a settings-connection. In particular, the settings-connection for an AddAndActivate() AC is set only after the authorization succeeds. Use the non-asserting variant of the function to fix the following failure:
nm_active_connection_get_settings_connection: assertion 'sett_conn' failed
1 _g_log_abort()
2 g_logv()
3 g_log()
4 _nm_g_return_if_fail_warning.constprop.14()
5 nm_active_connection_get_settings_connection()
6 active_connection_find()
7 _get_activatable_connections_filter()
8 nm_settings_get_connections_clone()
9 nm_manager_get_activatable_connections()
10 auto_activate_device_cb()
11 g_idle_dispatch()
12 g_main_context_dispatch()
13 g_main_context_iterate.isra.21()
14 g_main_loop_run()
15 main()
https://bugzilla.redhat.com/show_bug.cgi?id=1933719
Fixes: 33b9fa3a ('manager: Keep volatile/external connections while referenced by async_op_lst')