x11-fonts/font-manager: Attempt to fix build order bug (D29353)
Uncovered while building with devel/samurai but can probably also
happen with ninja eventually.
error: Package `Unicode-0.8.5' not found in specified Vala API directories or GObject-Introspection GIR directories
samu: subcommand failed
While here also remove explicit ninja dependency. It is already
pulled in through meson.
PR: 254678
Obtained from: upstream