It seems that the 0-RTT functionality doesn't work with the server and client in examples

[jawadbarbara]

The used commands :
To run the server :
python examples/http3_server.py --certificate tests/ssl_cert.pem --private-key tests/ssl_key.pem

Afterwards :
python examples/http3_client.py --ca-certs tests/pycacert.pem https://localhost:4433/