allowedExtensions doesn't work properly with final cut libraries

[stephane-archer]

  List<String>? paths = await FilePicker.platform.pickFileAndDirectoryPaths(
    type: FileType.custom,
    allowedExtensions: ["fcpbundle"],
  );

[stephane-archer]

the package macos_file_picker: ^0.6.1 doesn't suffer from this issue, it might be interesting to see what they do differently here