Does the GOG release includes them ?

Unfortunately not.

Makes me sad when developers make a definitive edition but forget to include content, I don't recall the game ever allowing pre orders on GOG so I don't think the GOG version ever had it.

Would be nice if the devs could add it back.

The Definitive Edition reportedly grants this skill automatically. From experience with other DLC like this, it may not activate until after the "tutorial" area of the game (i.e. wake up at home, acknowledge your debts to the crowd, and it ought to be there). Currently downloading DE so we'll see but that's what the internet is saying. Same goes for the Fireworks skill.

The Pet Shark skill- also a "prerelease" feature, has always been in the game. Just gotta go interact with a certain statue at a certain time of the day. ;)

Any news ?