Send Ophan attention time metrics for the YouTube player

[arelra]

We currently do not send Ophan attention metrics for the YouTube player

PR to implement for self hosted videos:
#14174

See chat thread here:
https://chat.google.com/room/AAAAG9rU0m0/iJ8LxBB0eSA/iJ8LxBB0eSA?cls=10