Resolve favicon not found (#94)

When some browsers load maproulette, the '/assets' route is sent to the API and results in the favicon not being found (http 404).
The deployment scripts shouldn't be sending '/assets' to the API and
should instead get the assets from the frontend container.

This resolves the missing favicon.

frontend/nginx-config

@@ -19,7 +19,7 @@ server {
         proxy_set_header Connection "upgrade";
         proxy_http_version 1.1;
     }
-    location ~ (/api/|/auth/|/docs/|/assets/) {
+    location ~ (/api/|/auth/|/docs/) {
         proxy_pass http://api;
 
         include mime.types;