Ilias 8 version for this sub-plugin

Looks like the Ilias 8 version of the main plugin is in flight https://github.com/DatabayAG/InteractiveVideo/issues/46 so I wanted to create an issue in this one to check in about updating it for Ilias 8 as well.

Thank you!

Copy of this related ticket https://github.com/DatabayAG/InteractiveVideoReference/issues/12