Describe the bug

If an error occurs that completes the future without releasing the semaphore then the calling thread may block forever.

https://github.com/apache/pulsar/blob/master/pulsar-client/src/main/java/org/apache/pulsar/client/impl/ProducerImpl.java#L354

There may be another case with timeout that tickles this but that's harder to reproduce

To Reproduce
Steps to reproduce the behavior:

Send a bunch of large messages asynchronously; hang

Expected behavior
Any failure path should release the semaphore before returning.

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: [e.g. iOS]

Additional context
Add any other context about the problem here.