Maintenance release that fixes a problem with displaying Scheduled Jobs page in the Dashboard UI for background jobs with an explicit queue specified.

• Changed – Populate the StateData property in return values of Monitoring API methods.
• Fixed – Scheduled Jobs page now works correctly for jobs with explicit queues defined.
• Project – Modernize project and its build environment to support new features.
• Project – Add tests for the net6.0 platform, remove netcoreapp1.0 and netcoreapp2.0 targets.