fix 规则引擎集群状态变化

jetlinks-manager/media-manager/src/main/java/org/jetlinks/community/media/sip/SipContext.java

@@ -6,8 +6,6 @@ import io.vavr.Tuple3;
 import lombok.extern.slf4j.Slf4j;
 import org.hswebframework.web.exception.BusinessException;
 import org.jetlinks.community.media.entity.SipGateway;
-import org.jetlinks.core.message.codec.Transport;
-import org.jetlinks.core.message.codec.Transports;
 
 import javax.sip.*;
 import javax.sip.header.ViaHeader;