Fix Swagger requests failed when accessed via nginx

Signed-off-by: dodo920306 <dodo920306@gmail.com>

Author: dodo920306

src/dashboard/cello.conf

@@ -20,7 +20,7 @@ server {
 
     location /api {
         proxy_pass http://cello-api-engine:8080;
-        proxy_set_header Host $host;
+        proxy_set_header Host $host:$server_port;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
         proxy_set_header X-Forwarded-Proto $scheme;