replace usage of _.extend with Object.assign

src/provision.js

@@ -28,8 +28,7 @@ const assert = require('assert'),
     paths = require('./paths.js'),
     users = require('./users.js'),
     tld = require('tldjs'),
-    tokens = require('./tokens.js'),
-    _ = require('underscore');
+    tokens = require('./tokens.js');
 
 // we cannot use tasks since the tasks table gets overwritten when db is imported
 const gProvisionStatus = {
@@ -245,7 +244,7 @@ async function getStatus() {
 
     const allSettings = await settings.list();
 
-    return _.extend({
+    return Object.assign({
         version: constants.VERSION,
         apiServerOrigin: settings.apiServerOrigin(), // used by CaaS tool
         webServerOrigin: settings.webServerOrigin(), // used by CaaS tool