Sanitize YouTube links

[Lurk]

Credit:
https://anticapitalist.party/@kropot/111099960211372703

[0x61nas]

The reason that makes us unable to write a pattern for it in the exit array is the changeable video ID, right?

[Lurk]

@0x61nas no. Exit vec is for unwrapping exit URLs.

For example: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjMuu2zrreBAxUt2gIHHaDVC_gQyCl6BAgqEAM&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DdQw4w9WgXcQ&usg=AOvVaw0aHtehaphMhOCAkCydRLZU&opi=89978449

Will be unwrapped to: https://www.youtube.com/watch?v=dQw4w9WgXcQ

What we want to achieve in this issue is that the 'remove' mode will remove the si query param but only if the host is youtube.com. I am not sure that we can just add si to ClinkConfig.params because maybe, in some cases (not YouTube), it is legitimate query param.