docs: sd-footnotes docs [skip chromatic]

[auroraVasconcelos]

Description:

Definition of Reviewable:

• [ ] Documentation is created/updated
• [ ] Migration Guide is created/updated
• [ ] E2E tests (features, a11y, bug fixes) are created/updated
• [ ] Stories (features, a11y) are created/updated
• [ ] relevant tickets are linked

[coraliefeil]

@auroraVasconcelos I think we need to hide the default story since we already show it at the top

Yes, pls

[coraliefeil]

Approved <3