Sanitize phone number field

To avoid this error:

You can't be redirected to payment page (error code 02305 : Invalid field format : MobilePhone : Must be composed from 1 to 14 numeric, ex : +00334916666666 or 00334916666666). Please contact us.

If the user phone number contains spaces, commas or other non numeric characters.

class-wc-gateway-payline.php

@@ -595,7 +595,7 @@ function generate_payline_form($order_id) {
 		$doWebPaymentRequest['buyer']['customerId'] = $order->billing_email;
 		$doWebPaymentRequest['buyer']['email'] = $doWebPaymentRequest['buyer']['customerId'];
 		$doWebPaymentRequest['buyer']['ip'] = $_SERVER['REMOTE_ADDR'];
-		$doWebPaymentRequest['buyer']['mobilePhone'] = $order->billing_phone;
+		$doWebPaymentRequest['buyer']['mobilePhone'] = preg_replace("/[^0-9.]/", '', $order->billing_phone);
 
 		// BILLING ADDRESS
 		$doWebPaymentRequest['billingAddress']['name'] = $order->billing_first_name." ".$order->billing_last_name;
@@ -609,7 +609,7 @@ function generate_payline_form($order_id) {
 		$doWebPaymentRequest['billingAddress']['cityName'] = $order->billing_city;
 		$doWebPaymentRequest['billingAddress']['zipCode'] = $order->billing_postcode;
 		$doWebPaymentRequest['billingAddress']['country'] = $order->billing_country;
-		$doWebPaymentRequest['billingAddress']['phone'] =  $order->billing_phone;
+		$doWebPaymentRequest['billingAddress']['phone'] = preg_replace("/[^0-9.]/", '', $order->billing_phone);
 
 		// SHIPPING ADDRESS
 		$doWebPaymentRequest['shippingAddress']['name'] = $order->shipping_first_name ." ".$order->shipping_last_name;
@@ -738,4 +738,4 @@ function payline_callback() {
 	    	}
     	}
 	}
-}
+}