[Typography] Manage `Helvetica Neue Arabic` font

[pylapp]

Context

OUDS will be used in projects with arabic-speaking people. Thus, text will be displayed in arabic. However the Helvetica Neue is designed for latin alphabet, not cyrllic nor arabic. That is the reason why there is an Helvetica Neue Arabic font which exists. The assets are available on the Brand website (need to be authenticated)

Description

Manage in the library the Helvetic Neue Arabic font and use it for arabic content.

Definition of Done

• Update the library to allow the use of this font
• Update documentation to explain how to use the fonts
• Update design system toolbox to embed the fonts and use it (maybe CI/CD changes required)

Notes

• Do not expose the font assets in our GitHub public external repositories
• As discussed offline with @B3nz01d it is acceptable to have snapshot tests not using these font; they still will be able to check some regressions whatever the font is (like weight, spacing, heights changes, etc)
• The Helvetica Neue Arabic has 3 weights: Light (45), Roman (55) and Bold (75)
• PostScript name of these values are respectively: HelveticaNeueLTArabic-Light, HelveticaNeueLTArabic-Roman and HelveticaNeueLTArabic-Bold