nginx: fix bad Content-Type on package metadata

Author: rmg

nginx.conf

@@ -11,10 +11,9 @@ events {
 http {
     # We literally only care about 2 types of files/payloads.
     types {
-        application/json                      json;
         application/gzip                      tgz;
     }
-    default_type  application/octet-stream;
+    default_type  application/json;
     sendfile        on;
     keepalive_timeout  65;
     proxy_cache_path  /tmp/npm/cache levels=1:2 keys_zone=NPM:10m inactive=90d max_size=5g;
@@ -32,7 +31,6 @@ http {
         local ephemeralNPM = require "ephemeral-npm"
         ephemeralNPM.init()
     }
-
     server {
         listen       4873;
         set $npm_config_registry '';