获取相册时，如果用户（iOS 14以上系统）选择了部分图片允许访问，那么这就需要更新相册的访问权限等级了，不然是拿不到limited的status的：参考
https://www.wwdcnotes.com/notes/wwdc20/10641/
if #available(iOS 14, *) {
let requiredAccessLevel: PHAccessLevel = .readWrite
PHPhotoLibrary.requestAuthorization(for: requiredAccessLevel) { (authorizationStatus) in
switch authorizationStatus{
case .limited:
Logger.log("相册部分")
case .authorized:
Logger.log("相册允许")
default:
Logger.log("相册Unimplemented")
}
}
} else {
let photoStatus = PHPhotoLibrary.authorizationStatus()
Logger.log("系统14以下用户相册权限\(photoStatus.rawValue)")
// Fallback on earlier versions
}
