models/schedule: order choices alphabetically (#129)

voir ticket rc/aircox#128

Co-authored-by: Christophe Siraut <d@tobald.eu.org>
Reviewed-on: rc/aircox#129
Co-authored-by: Chris Tactic <chris@tacticasbl.be>
Co-committed-by: Chris Tactic <chris@tacticasbl.be>

aircox/models/schedule.py

@@ -55,7 +55,7 @@ class Schedule(Rerun):
         _("timezone"),
         default=current_timezone_key,
         max_length=100,
-        choices=[(x, x) for x in zoneinfo.available_timezones()],
+        choices=sorted([(x, x) for x in zoneinfo.available_timezones()]),
         help_text=_("timezone used for the date"),
     )
     duration = models.TimeField(