fix response `content-type` is not set if access without access token

Kairlec

2023-05-15 ca103731c721aae3f5f622e58c679ed5c09fd9e9

 src/main/java/com/genersoft/iot/vmp/gb28181/transmit/event/response/impl/CancelResponseProcessor.java

@@ -17,7 +17,7 @@
@Component
public class CancelResponseProcessor extends SIPResponseProcessorAbstract {

   private String method = "CANCEL";
   private final String method = "CANCEL";

   @Autowired
   private SipLayer sipLayer;