Backport of "player: Fix get_current_subtitle_track annotation" into 1.18
requested to merge tpm/gst-plugins-bad:backport-mr-1775-into-1.18-player-current-sub-annotation into 1.18
Backport of !1775 (merged) "player: Fix get_current_subtitle_track annotation".
Commits:
- d4df91cd player: Fix get_current_subtitle_track annotation