Resolve "Show imported extra lessons and events in substitutions table"

Closes #73 (closed)

aleksis/apps/untis/util/mysql/importers/absences.py

@@ -158,6 +158,7 @@ def import_absences(
                     datetime_end=affected_event["DTEND"].dt,
                     defaults=dict(
                         cancelled=True,
+                        current_change=True,
                         slot_number_start=ref_object.slot_number_start,
                         slot_number_end=ref_object.slot_number_end,
                     ),