Get current SSID by CF-based APIs

CurrentSSID.swift

// https://forums.developer.apple.com/thread/50302
func getSSID() -> [String] {
    guard let interfacesName = CNCopySupportedInterfaces() as? [String] else { return [String()] }
    
    return interfacesName.compactMap({ (name) in
        guard let info = CNCopyCurrentNetworkInfo(name as CFString) as? [String: AnyObject] else { return nil }
        guard let ssid = info[kCNNetworkInfoKeySSID as String] as? String else { return nil }
        return ssid
    })
}