[OUDS] Docs: Add visually-hidden to side menu of the docs

[louismaximepiton]

Note: Please transform - [ ] into - (NA) in the description when things are not applicable

Related issues

Resolves #2612 (comment)

Description

Add a <span class="visually-hidden"> to convey the information that the page isn't ready yet without even clicking on the link.

Motivation & Context

Better a11y.

Types of change

• New feature (non-breaking change which adds functionality)

Live previews

• https://deploy-preview-2623--boosted.netlify.app/docs

Checklist

Contribution

• I have read the contributing guidelines

Accessibility

• My change follows accessibility good practices; I have at least run axe

Development

• My change follows the developer guide
• (NA) I have added JavaScript unit tests to cover my changes
• (NA) I have added SCSS unit tests to cover my changes

Documentation

• My change introduces changes to the documentation and/or I have updated the documentation accordingly

Checklist (for Core Team only)

• (NA) My change introduces changes to the migration guide
• (NA) My new component is well displayed in Storybook
• (NA) My new component is compatible with RTL
• Manually run BrowserStack tests
• Manually test browser compatibility with BrowserStack (Chrome >= 60, Firefox >= 60 (+ ESR), Edge, Safari >= 12, iOS Safari, Chrome & Firefox on Android)
• Code review
• Design review
• A11y review

After the merge

• Manually launch Percy tests

[netlify]

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