Switch from the bostom dataset to the toy dataset

[thibaultcordier]

Description

Documentation construction is interrupted due to the inaccessibility of the bostom dataset, which fails the current PR. We propose to switch from the bostom dataset to the toy dataset.

Fixes #460

Type of change

Please remove options that are irrelevant.

• This change requires a documentation update

How Has This Been Tested?

• [x] Code execution: ok

Checklist

• [x] I have read the contributing guidelines
• [x] I have updated the HISTORY.rst and AUTHORS.rst files
• [x] Linting passes successfully : make lint
• [x] Typing passes successfully : make type-check
• [x] Unit tests pass successfully : make tests
• [x] Coverage is 100% : make coverage
• [x] Documentation builds successfully : make doc