[Doc] Add disabled label to disabled file input

[MewenLeHo]

Description

In current documentation, the label for the disabled input file is missing a .is-disabled class.

Whereas it should look like:

Motivation & Context

Make all disabled form element consistent across the documentation.

Types of change

• Bug fix (non-breaking which fixes an issue)

Live previews

• https://deploy-preview-2222--boosted.netlify.app/docs/5.3/forms/form-control/#file-input

Checklist

Contribution

• I have read the contributing guidelines

Accessibility

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

Design

• [na] My change respects the design guidelines defined in Orange Design System
• [na] My change is compatible with a responsive display

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

• [na] 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
• [na] Manually run BrowserStack tests
• [na] Manually test browser compatibility with BrowserStack (Chrome >= 60, Firefox >= 60 (+ ESR), Edge, Safari >= 12, iOS Safari, Chrome & Firefox on Android)
• Code review
• [na] Design review
• [na] A11y review

After the merge

• Manually launch Percy tests

[netlify]

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[louismaximepiton]

Good catch!