[release] 0.66.1 - Explicitly set Connection: close headers with log_event request (#470)

### Fixes
- Seeing increase ennconreset error for logevent since we refactor code
to use request.session() instead of request. This is due to
request.session() keep connection open by sending extra header
Connection: keep-alive





>Included In This Release
>- 93cc104 Xin Li
>   - network: explicitly close connection for log event (#469)

Author: xinlili-statsig

statsig/version.py

@@ -1 +1 @@
-__version__ = '0.66.0'
+__version__ = '0.66.1'