Add filter to save_payment_method_checkbox

Allow the save payment method checkbox to be removed based on payment gateway settings.

includes/abstracts/abstract-wc-payment-gateway.php

@@ -516,7 +516,7 @@ abstract class WC_Payment_Gateway extends WC_Settings_API {
 	 * @since 2.6.0
 	 */
 	public function save_payment_method_checkbox() {
-		printf(
+		$html = sprintf(
 			'<p class="form-row woocommerce-SavedPaymentMethods-saveNew">
 				<input id="wc-%1$s-new-payment-method" name="wc-%1$s-new-payment-method" type="checkbox" value="true" style="width:auto;" />
 				<label for="wc-%1$s-new-payment-method" style="display:inline;">%2$s</label>
@@ -524,6 +524,8 @@ abstract class WC_Payment_Gateway extends WC_Settings_API {
 			esc_attr( $this->id ),
 			esc_html__( 'Save to account', 'woocommerce' )
 		);
+		
+		echo apply_filters( 'woocommerce_payment_gateway_save_new_payment_method_option_html', $html, $this );
 	}
 
 	/**