[gnome-control-center] network: Fix warnings after removing a VPN

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit c37ab4032b2b74b24dfede356e5b351619f354f8
Author: Robert Ancell <robert ancell canonical com>
Date:   Wed Nov 13 09:56:19 2019 +1300

    network: Fix warnings after removing a VPN
    
    This is due to the object being accessed after being unreffed - connect the signal
    so it is removed when the object is finalized.
    
    This regression was introduced in 93a269f8 when switching to GtkTemplate.

 panels/network/net-vpn.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
---
diff --git a/panels/network/net-vpn.c b/panels/network/net-vpn.c
index b350e0de4..97925b80f 100644
--- a/panels/network/net-vpn.c
+++ b/panels/network/net-vpn.c
@@ -146,7 +146,6 @@ static void
 editor_done (NetVpn *self)
 {
         nm_device_refresh_vpn_ui (self);
-        g_object_unref (self);
 }
 
 static void
@@ -164,7 +163,7 @@ edit_connection (NetVpn *self)
         title = g_strdup_printf (_("%s VPN"), nm_connection_get_id (self->connection));
         net_connection_editor_set_title (editor, title);
 
-        g_signal_connect_swapped (editor, "done", G_CALLBACK (editor_done), g_object_ref (self));
+        g_signal_connect_object (editor, "done", G_CALLBACK (editor_done), self, G_CONNECT_SWAPPED);
         net_connection_editor_run (editor);
 }