fix websocket connection issue in docker makeplane/plane#3195

[abidkhan484]

Since the proxy server is running with Nginx, it is recommended to add the relevant proxy header to use Web Socket. The relevant documentation is shared below.

Reference: Nginx WebSocket Proxying documentation

[abidkhan484]

good to go

Thank you for your thorough review of my pull request. Your insights were incredibly helpful, and I appreciate your time and expertise.