fix sign setting

Helius

2022-05-10 779298eb527bce4c508ea9d1b050c4a795dddebe

 src/main/java/cc/mrbird/febs/pay/properties/AliPayProperties.java

@@ -21,4 +21,6 @@
    private String privateKey;

    private String noticeUrl;

    private String domain;
}