- Deduplicate "libraries" in pkgg.generate()
  Fixes:
    libgxps/meson.build:101: WARNING: Keyword argument "libraries"
    defined multiple times.
    WARNING: This will be an error in future Meson releases.
- Increase required meson_version from 0.43.0 to 0.50.0 due to usage
  of install arg in libgxps/meson.build:63:
  Fixes:
    WARNING: Project targeting '>= 0.43.0' but tried to use feature
    introduced in '0.50.0': install arg in configure_file.