change readme for 0.3.0 release (#459)

### What problem does this PR solve?


### Type of change

- [x] Documentation Update

docker/docker-compose.yml

@@ -9,9 +9,10 @@ services:
         condition: service_healthy
       es01:
         condition: service_healthy
-    image: infiniflow/ragflow:v0.2.0
+    image: infiniflow/ragflow:${RAGFLOW_VERSION}
     container_name: ragflow-server
     ports:
+      - ${SVR_HTTP_PORT}:9380
       - ${SVR_HTTP_PORT}:9380
       - 80:80
       - 443:443