[MINOR] fix: Add a missing bracket in log when getting shuffle index using Netty (apache#1815)

### What changes were proposed in this pull request?

Add a missing bracket in log when getting shuffle index using Netty.

### Why are the changes needed?

A better log format.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

No need.

Author: dingshun3016

internal-client/src/main/java/org/apache/uniffle/client/impl/grpc/ShuffleServerGrpcNettyClient.java

@@ -325,7 +325,8 @@ public RssGetShuffleIndexResponse getShuffleIndex(RssGetShuffleIndexRequest requ
             + "], shuffleId["
             + request.getShuffleId()
             + "], partitionId["
-            + request.getPartitionId();
+            + request.getPartitionId()
+            + "]";
     long start = System.currentTimeMillis();
     int retry = 0;
     RpcResponse rpcResponse;