Create an .env variable for Server Listening port - to sync the setti…

[zzecool]

…ng to nginx

What problem does this PR solve?

If you manual change the listening port of Server to somthing like this:

services: ragflow: depends_on: mysql: condition: service_healthy es01: condition: service_healthy image: infiniflow/ragflow:v1.0 container_name: ragflow-server ports: - ${SVR_HTTP_PORT}:9380 - 3000:80 - 443:443

nginx fails to server the server because the Listening port is hardcoded in ragflow.conf

Issue link:#[Link the issue here]

Type of change

• [ ] Bug Fix (non-breaking change which fixes an issue)