[FEATURE/CHANGE] Add A380X stable direct download links

[FoxtrotSierra6829]

Suggested feature/change

Add the A380X stable direct download links to https://flybywiresim.com/downloads/

Explain the feature/change(if applicable)

direct link for stable 4K version is:

• https://github.com/flybywiresim/aircraft/releases/download/assets/stable/A380X-stable-4K.7z

the stable 8K version is split in 3 parts:

• https://github.com/flybywiresim/aircraft/releases/download/assets/stable/A380X-stable-8K.7z.001
• https://github.com/flybywiresim/aircraft/releases/download/assets/stable/A380X-stable-8K.7z.002
• https://github.com/flybywiresim/aircraft/releases/download/assets/stable/A380X-stable-8K.7z.003

Unfortunately the current DownloadLinks component does not allow for the provision of only stable links and does not allow for the download to be split in multiple parts. Changes are thus required both in

website/src/pages/downloads/index.tsx

Line 45 in 097b526

<DownloadLinks aircraft="A380X" stableLink="" devLink="" />

and

website/src/components/Downloads/DownloadLinks.tsx

Line 11 in 097b526

const downloadLinks = ({ stableLink, devLink, aircraft }: DownloadProps) => (