Fix data URLs of compguesswhat dataset
_The documentation is not available anymore as the PR was closed or merged._
After we informed the `compguesswhat` dataset authors about an error with their data URLs, they have updated them:
- https://github.com/CompGuessWhat/compguesswhat.github.io/issues/1

This PR updates their data URLs in our loading script.

Related to:
- #3191