Fix sokoban and arkanoid repo confusion

[aureliojargas]

• https://github.com/aureliojargas/sed-scripts
• https://github.com/aureliojargas/sokoban.sed

Sokoban is in both, and also in my website:

• https://aurelio.net/sed/sokoban/sokoban.sed
• https://aurelio.net/sed/sokoban/sokoban.sed.html
• https://aurelio.net/projects/sedsokoban/sokoban.sed.html
• https://aurelio.net/projects/sedsokoban/sedsokoban.zip

How many more copies do I need? 😂