Starts the capture session

StartCaptureSession.swift

    /// - Tag: Start capture session
    
    public func start() {
//        We use our capture session queue to ensure our UI runs smoothly on the main thread.
        sessionQueue.async {
            if !self.isSessionRunning && self.isConfigured {
                switch self.setupResult {
                case .success:
                    self.session.startRunning()
                    self.isSessionRunning = self.session.isRunning
                    
                    if self.session.isRunning {
                        DispatchQueue.main.async {
                            self.isCameraButtonDisabled = false
                            self.isCameraUnavailable = false
                        }
                    }
                    
                case .configurationFailed, .notAuthorized:
                    print("Application not authorized to use camera")

                    DispatchQueue.main.async {
                        self.alertError = AlertError(title: "Camera Error", message: "Camera configuration failed. Either your device camera is not available or its missing permissions", primaryButtonTitle: "Accept", secondaryButtonTitle: nil, primaryAction: nil, secondaryAction: nil)
                        self.shouldShowAlertView = true
                        self.isCameraButtonDisabled = true
                        self.isCameraUnavailable = true
                    }
                }
            }
        }
    }