update cron module

CronJob -> CronJob.from
CronJob(time) -> CronTime

src/scheduler.js

@@ -10,7 +10,7 @@ const apps = require('./apps.js'),
     assert = require('assert'),
     BoxError = require('./boxerror.js'),
     constants = require('./constants.js'),
-    CronJob = require('cron').CronJob,
+    { CronJob } = require('cron'),
     debug = require('debug')('box:scheduler'),
     docker = require('./docker.js'),
     safe = require('safetydance'),
@@ -81,7 +81,7 @@ async function createJobs(app, schedulerConfig) {
             cronTime = (constants.TEST ? '*/5 ' : `${Math.floor(60*Math.random())} `) + schedule; // time ticks faster in tests
         }
 
-        const cronJob = new CronJob({
+        const cronJob = CronJob.from({
             cronTime,
             onTick: async () => {
                 const [error] = await safe(runTask(appId, taskName)); //  put the app id in closure, so we don't use the outdated app object by mistake