[bug] getting "HTTP/1.1 501 Not Implemented"

Describe the bug

hi,
i like the idea of your proxy, but, getting HTTP/1.1 501 Not Implemented for curl -v --proxy http://localhost:8080 -k https://worldtimeapi.org/api/timezone/Asia/Jerusalem.
what am i missing? how can i make it work?

Logs

user1@user1-pc:~/Downloads$ curl -v --proxy http://localhost:8080 -k https://worldtimeapi.org/api/timezone/Asia/Jerusalem
*   Trying 127.0.0.1:8080...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 8080 (#0)
* allocate connect buffer!
* Establish HTTP proxy tunnel to worldtimeapi.org:443
> CONNECT worldtimeapi.org:443 HTTP/1.1
> Host: worldtimeapi.org:443
> User-Agent: curl/7.68.0
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 501 Not Implemented
< 
* Received HTTP code 501 from proxy after CONNECT
* CONNECT phase completed!
* Closing connection 0
curl: (56) Received HTTP code 501 from proxy after CONNECT

Additional information

see Reproduction url for code

Reproduction

https://jsfiddle.net/g2fk1vph/

La issue non indica file del repository, test o punti di ingresso. Inizia riproducendo la richiesta curl CONNECT verso il proxy e segui come vengono gestite le richieste CONNECT; il lavoro è completato quando la richiesta HTTPS ha esito positivo attraverso il proxy e un test di regressione copre questo caso.