[gnome-calendar] Use Unicode en dash in a translatable string

[Piotr Drąg <piotrdrag src gnome org>]

commit c5d92c22d591193d3cb9f9aa19d50ee210472fc7
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Tue Jan 17 15:21:52 2017 +0100

    Use Unicode en dash in a translatable string
    
    See https://developer.gnome.org/hig/stable/typography.html
    
    https://bugzilla.gnome.org/show_bug.cgi?id=772263

 src/gcal-quick-add-popover.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/gcal-quick-add-popover.c b/src/gcal-quick-add-popover.c
index 672a0c5..d5d91c5 100644
--- a/src/gcal-quick-add-popover.c
+++ b/src/gcal-quick-add-popover.c
@@ -277,7 +277,7 @@ update_header (GcalQuickAddPopover *self)
               end_hour = g_date_time_format (self->date_end, "%I:%M %P");
             }
 
-          title_date = g_strdup_printf (_("New Event on %s, %s - %s"),
+          title_date = g_strdup_printf (_("New Event on %s, %s – %s"),
                                         start,
                                         start_hour,
                                         end_hour);