0.22.8

Alba Mendez:
      fix typo in ObjectExt::property_value docs

Sebastian Dröge:
      Update gir / gir-files
      Regenerate with latest gir / gir-files
      gio: Add forgotten socket_msg_flags modules to lib.rs
      Add various missing Gir.toml checks
      Remove various unused dependencies
      gio: Fix code style
      gio-unix: Fix order of types in Gir.toml
      gio: Add missing `unsafe`
      Add AI contribution policy section to the README.md
      Update Cargo.lock
      Update versions to 0.22.8

Tau Gärtli:
      Add safe wrapper for g_log_writer_default_set_debug_domains

Tomoaki Kawada:
      glib: gate `BookmarkFile` with `cfg(feature = "v2.76")`
      glib: remove `g_bookmark_file_copy` polyfill
      glib: require `A: 'static` in `Variant::from_data[_with_type][_trusted]`