[Enhancement] Fixed asynchronous send backpressure capability

[guyinyou]

Before Creating the Enhancement Request

• I have confirmed that this should be classified as an enhancement rather than a bug/feature.

Summary

Fixed asynchronous send backpressure capability

Motivation

The semaphore should be released after sending the callback. Otherwise, it will not have the effect of back pressure.

Describe the Solution You'd Like

Release the semaphore in sendCallBack

Describe Alternatives You've Considered

After turning on backpressure, it can be sent asynchronously at the expected rate limit.

Additional Context

No response