[gimp] Show message dialogs in preferences dialog

[Jehan <jehanp src gnome org>]

commit ac0a084e6e007cc0b035c5f8f351d4c157cfb2fe
Author: Luca Bacci <luca bacci982 gmail com>
Date:   Wed Aug 11 10:49:35 2021 +0200

    Show message dialogs in preferences dialog

 app/dialogs/preferences-dialog.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)
---
diff --git a/app/dialogs/preferences-dialog.c b/app/dialogs/preferences-dialog.c
index 43422098cd..d34f732a96 100644
--- a/app/dialogs/preferences-dialog.c
+++ b/app/dialogs/preferences-dialog.c
@@ -1068,10 +1068,9 @@ prefs_message (GtkMessageType  type,
                                    type, GTK_BUTTONS_OK,
                                    "%s", message);
 
-  g_signal_connect (dialog, "response",
-                    G_CALLBACK (gtk_widget_destroy),
-                    NULL);
-  gtk_widget_show (dialog);
+  gtk_dialog_run (GTK_DIALOG (dialog));
+
+  gtk_widget_destroy (dialog);
 }
 
 static GtkWidget *