Fixing invalid agent issue (#1904)

lib/adapters/http.js

@@ -85,10 +85,7 @@ module.exports = function httpAdapter(config) {
       method: config.method.toUpperCase(),
       headers: headers,
       agent: agent,
-      agents: {
-        httpsAgent: config.httpsAgent,
-        httpAgent: config.httpAgent
-      },
+      agents: { http: config.httpAgent, https: config.httpsAgent },
       auth: auth
     };