chore. remove deprecated api

android/src/main/java/com/syan/agora/AgoraModule.java

                 public void run() {
                     WritableMap statsMap = Arguments.createMap();
                     statsMap.putInt("uid", stats.uid);
-                    statsMap.putInt("delay", stats.delay);
                     statsMap.putInt("receivedBitrate", stats.receivedBitrate);
                     statsMap.putInt("receivedFrameRate", stats.receivedFrameRate);
                     statsMap.putInt("rxStreamType", stats.rxStreamType);

ios/RCTAgora/RCTAgora.m

   [self sendEvent:RemoteVideoStats params:@{
                                             @"stats": @{
                                                 @"uid": @(stats.uid),
-                                                @"delay": @(stats.delay),
                                                 @"width": @(stats.width),
                                                 @"height": @(stats.height),
                                                 @"receivedBitrate": @(stats.receivedBitrate),