Add WC Product CSV Exporter limit filter

with tons of products is nice to have an way to change the limit for the exporter (now is set to 50)

'''php
function wc_exporter_set_limit($limit) {
  return 1000;
}
add_filter( 'woocommerce_product_export_product_default_limit', 'wc_exporter_set_limit');
'''

includes/export/class-wc-product-csv-exporter.php

@@ -50,6 +50,7 @@ class WC_Product_CSV_Exporter extends WC_CSV_Batch_Exporter {
 	 */
 	public function __construct() {
 		parent::__construct();
+		$this->set_limit(apply_filters( "woocommerce_product_export_{$this->export_type}_default_limit", $this->limit));
 		$this->set_product_types_to_export( array_merge( array_keys( wc_get_product_types() ), array( 'variation' ) ) );
 	}