Restriction key must not include timestamp parameter

[mauriciofierrom]

When playing a section, the t=n query param is sometimes appended to the key used to store the timestamp for manual play check for the YouTube player in local storage. This makes for duplicate entries and checks failure.

We should either make sure only the video id param is included v=<video-id> or change this part of the key altogether (perhaps to use only the video id and not the whole URL).