[gimp] app: show time of last version update check.

[Jehan <jehanp src gnome org>]

commit a05b08511242f975ae63f8c814d104bf803bf62e
Author: Jehan <jehan girinstud io>
Date:   Mon Mar 30 14:52:18 2020 +0200

    app: show time of last version update check.
    
    As noted on IRC, after the first update check on a given day, it looks
    like the check button does nothing. Therefore also display the check
    time to clearly show the button click was taken into account (simply
    there are no updates, hence only displayed check time is updated).

 app/dialogs/about-dialog.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/app/dialogs/about-dialog.c b/app/dialogs/about-dialog.c
index d767d830f0..b4af6de51e 100644
--- a/app/dialogs/about-dialog.c
+++ b/app/dialogs/about-dialog.c
@@ -350,12 +350,15 @@ about_dialog_add_update (GimpAboutDialog *dialog,
   if (config->check_update_timestamp > 0)
     {
       gchar *subtext;
+      gchar *time;
 
       datetime = g_date_time_new_from_unix_local (config->check_update_timestamp);
       date = g_date_time_format (datetime, "%x");
-      subtext = g_strdup_printf (_("Last checked on %s"), date);
+      time = g_date_time_format (datetime, "%X");
+      subtext = g_strdup_printf (_("Last checked on %s at %s"), date, time);
       g_date_time_unref (datetime);
       g_free (date);
+      g_free (time);
 
       text = g_strdup_printf ("%s\n<i>%s</i>",
                               _("Check for updates"), subtext);