How to reproduce:
1. Open the attached project
2. Change the IP addresses to yours in the PythonServer/bounce.py and Assets/Request.cs scripts
3. Build the project
4. Open the built Player on other machine
5. Start the python server (python3 PythonServer/bounce.py)
6. On the client machine, keep pressing "Connect"
7. On the client machine, check open network connections (using netstat)

Actual result: The client creates different connection for each request (the connection stays alive).
Expected result: The opened connection has to be closed or the requests have to go through the same connection.

Reproducible with: 2020.1.0a8, 2019.3.0b6, 2019.2.8f1, 2018.4.11f1, 2017.4.33f1.