title: .NET Core Worker service does not have CRON
body: <p>I'm working with .net core 3.1 worker service
  The worker contains cron job with this Nuget package CronScheduler.Extensions v3.0.0
  I completed project in my development env.(everything OK and No error) and im going to serve in production and install the worker with sc.exe
  when i start the worker service something went wrong and i have a following error from the event viewer log</p>
  
  <p>Category: CronScheduler.Extensions.Internal.SchedulerRegistration
  EventId: 101</p>
  
  <p>[Job][WasJob] does not have CRON: . Task will not run.</p>
  
  <p>How can i fix this problem any idea?
  Thanks for answers.</p>