Link to download the training text in docs/source/quicktour.rst is broken

[14jdelap]

In Quicktour the link to download the wikitext-103 file is broken because the response is a 403.

➜  tokenizer-training wget https://s3.amazonaws.com/research.metamind.io/wikitext/wikitext-103-raw-v1.zip
--2024-05-09 12:39:46--  https://s3.amazonaws.com/research.metamind.io/wikitext/wikitext-103-raw-v1.zip
Resolving s3.amazonaws.com (s3.amazonaws.com)... 3.5.12.14, 52.216.89.134, 52.217.197.112, ...
Connecting to s3.amazonaws.com (s3.amazonaws.com)|3.5.12.14|:443... connected.
HTTP request sent, awaiting response... 403 Forbidden
2024-05-09 12:39:46 ERROR 403: Forbidden.