dash: rewrite `_getLastSegmentStart` for SegmentTemplate-based MPD to better evaluate the last segment of a static MPD
dash: rewrite `_getLastSegmentStart` for SegmentTemplate-based MPD to better evaluate the last segment of a static MPD

canalplus/rx-player,canalplus/rx-player,canalplus/rx-player,canalplus/rx-player,canalplus/rx-player