[Improvement] Remove the ShuffleBlockInfo used in the communication between client and server via handleSendShuffleDataRequest.

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)

### Search before asking

- [X] I have searched in the [issues](https://github.com/apache/incubator-uniffle/issues?q=is%3Aissue) and found no similar issues.

### What would you like to be improved?

1. Remove the ShuffleBlockInfo used in the communication between client and server via handleSendShuffleDataRequest.
2. The code `byteBuf.writeInt(shuffleBlockInfo.getLength());` in encodeShuffleBlockInfo is redundant, because the block data length has been encoded in `shuffleBlockInfo.copyDataTo(byteBuf)`

Related PR: #2181

### How should we improve?

_No response_

### Are you willing to submit PR?

- [X] Yes I am willing to submit a PR!

Review related PR #2181 first, then trace handleSendShuffleDataRequest and encodeShuffleBlockInfo to understand the client-server communication path. Check how ShuffleBlockInfo.copyDataTo(byteBuf) encodes the block length. Done means removing the redundant ShuffleBlockInfo usage and length encoding without breaking the request protocol.

Written by the indexing model from the issue text.