build-export: Document --end-of-life
build-export: Document --end-of-life

This option was added without documentation.

Closes: #2524
Approved by: mwleeds

flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,flatpak/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak