change upstream from hunchentoot to hot-line.

I was getting errors with the previous nginx config.

conf/hot-line-prod.conf

@@ -1,4 +1,4 @@
-upstream hunchentoot {
+upstream hot-line {
     server 127.0.0.1:3002;
 }
  
@@ -24,7 +24,7 @@ server {
         # if the requested file does not exist then
         # proxy to the hunchentoot server cluster
         if (!-f $request_filename) {
-            proxy_pass http://hunchentoot;
+            proxy_pass http://hot-line;
         }
     }
 }