Fix the stream client python package name (#4703)

---

### Motivation

```
WARNING  Error during upload. Retry with the --verbose option for more details.
ERROR    HTTPError: 400 Bad Request from https://upload.pypi.org/legacy/
         Filename 'apache-bookkeeper-client-4.17.3.tar.gz' is invalid, should be 'apache_bookkeeper_client-4.17.3.tar.gz'.
```

Author: zymap

stream/clients/python/setup.py

@@ -17,7 +17,7 @@
 
 # Package metadata.
 
-name = 'apache-bookkeeper-client'
+name = 'apache_bookkeeper_client'
 description = 'Apache BookKeeper client library'
 version = '4.18.0'
 # Should be one of: