Convert Scheduler to dotnet 8.0

The OrigamScheduler project is currently a .NET 4.7.2 service. It should be converted to dotnet 8.0 because .NET 4.7.2 is not compatible with windows nano server that we use as a base for our docker images.

It should run with Linux images, too, if possible.

Scheduler can now run as a console application (on windows or linux) as well as a windows service.

sc create "OrigamScheduler" binPath="C:\Windows\System32\cmd.exe\OrigamScheduler.exe"

sc startOrigamScheduler
sc query OrigamScheduler

Not actually tested on linux.