替换一个过时的API，解决maven打包警告

xiaoxie

2022-05-01 260bfd5935b87edd4e09a2d77b9536d0e85dde47

 src/main/java/com/genersoft/iot/vmp/gb28181/utils/SipUtils.java

@@ -25,6 +25,7 @@
     * */
    public static String getChannelIdFromHeader(Request request) {
        Header subject = request.getHeader("subject");
        if (subject == null) return null;
        return ((Subject) subject).getSubject().split(":")[0];
    }