[ghex] appwin: Fix markup on tab-close dialogs

[Logan Rathbone <larathbone src gnome org>]

commit 37f3a1b105dc977285690a7b7ed6c79532794735
Author: Logan Rathbone <poprocks gmail com>
Date:   Sun Apr 10 22:24:19 2022 -0400

    appwin: Fix markup on tab-close dialogs

 src/ghex-application-window.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/src/ghex-application-window.c b/src/ghex-application-window.c
index 0c6aef7..da42cc4 100644
--- a/src/ghex-application-window.c
+++ b/src/ghex-application-window.c
@@ -520,7 +520,8 @@ close_doc_confirmation_dialog (GHexApplicationWindow *self,
                        GTK_DIALOG_MODAL | GTK_DIALOG_DESTROY_WITH_PARENT,
                        GTK_MESSAGE_QUESTION,
                        GTK_BUTTONS_NONE,
-                       "%s",
+                       NULL);
+       gtk_message_dialog_set_markup (GTK_MESSAGE_DIALOG (dialog),
                        message);
        g_free (message);