Fix clearing episode flags not working with full trakt sync.
(cherry picked from commit 1a96f93)
Do null check on return value, to be safe.

- https://github.com/UweTrottmann/SeriesGuide/issues/371
(cherry picked from commit b9d09c7)
Push version to 12.4, 244.
Change log for 12.4.
Merge branch 'fix-12.4'