updateCenter.post(
{"connectionCheckUrl":"https://www.go

java.io.IOException: Could not find JSON in http://updates.jenkins-ci.org/update-center.json?id=default&version=2.476
        at hudson.model.DownloadService.loadJSON(DownloadService.java:129)
        at hudson.model.UpdateSite.updateDirectlyNow(UpdateSite.java:217)
        at hudson.model.UpdateSite.updateDirectlyNow(UpdateSite.java:212)
        at hudson.model.UpdateCenter.updateAllSitesNow(UpdateCenter.java:2866)
        at jenkins.security.ImpersonatingScheduledExecutorService$1.run(ImpersonatingScheduledExecutorService.java:67)
        at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
        at java.base/java.lang.Thread.run(Thread.java:840)

SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data