bug about dolphinscheduler-remote SendAsync (#6972)

* bug about SendAsync

dolphinscheduler-remote/src/main/java/org/apache/dolphinscheduler/remote/future/ResponseFuture.java

@@ -105,6 +105,10 @@ public class ResponseFuture {
         return FUTURE_TABLE.get(opaque);
     }
 
+    public void removeFuture() {
+        FUTURE_TABLE.remove(opaque);
+    }
+
     /**
      * whether timeout
      *

dolphinscheduler-remote/src/main/java/org/apache/dolphinscheduler/remote/handler/NettyClientHandler.java

@@ -136,6 +136,7 @@ public class NettyClientHandler extends ChannelInboundHandlerAdapter {
             future.setResponseCommand(command);
             future.release();
             if (future.getInvokeCallback() != null) {
+                future.removeFuture();
                 this.callbackExecutor.submit(future::executeInvokeCallback);
             } else {
                 future.putResponse(command);