Calendar urls: replace slug by extra

tracim/tracim/lib/calendar.py

 CALENDAR_TYPE_USER = UserCalendar
 CALENDAR_TYPE_WORKSPACE = WorkspaceCalendar
 
-CALENDAR_BASE_URL = '{proto}://{domain}:{port}'
+CALENDAR_BASE_URL_TEMPLATE = '{proto}://{domain}:{port}'
 CALENDAR_USER_URL_TEMPLATE = \
-    CALENDAR_BASE_URL + '/user/{id}.ics#{slug}'
+    CALENDAR_BASE_URL_TEMPLATE + '/user/{id}.ics{extra}/'
 CALENDAR_WORKSPACE_URL_TEMPLATE = \
-    CALENDAR_BASE_URL + '/workspace/{id}.ics#{slug}'
+    CALENDAR_BASE_URL_TEMPLATE + '/workspace/{id}.ics{extra}/'
 
 
 class CalendarManager(object):

tracim/tracim/model/auth.py

             domain=cfg.RADICALE_CLIENT_HOST or request.domain,
             port=cfg.RADICALE_CLIENT_PORT,
             id=self.user_id,
-            slug=slugify(self.get_display_name(
+            extra='#' + slugify(self.get_display_name(
                 remove_email_part=True
             ), only_ascii=True)
         )

tracim/tracim/model/data.py

             domain=cfg.RADICALE_CLIENT_HOST or tg.request.domain,
             port=cfg.RADICALE_CLIENT_PORT,
             id=self.workspace_id,
-            slug=slugify(self.label)
+            extra='#' + slugify(self.label),
         )
 
     def get_user_role(self, user: User) -> int: