Remove usage of OpenStudio Workflow Gem from OpenStudio Server

[DavidGoldwasser]

This is in preparation for eventually removing the Workflow Gem from OpenStudio when we decide to drop support for class mode.

[brianlball]

Tracking down the dependency chain for workflow-gem results in:

• OSAF
  • URBANopt
    • urbanopt-core-gem
    • urbanopt-reporting-gem
    • urbanopt-reopt-gem
      • openstudio-extension-gem
        • workflow-gem

so we need to remove these dependency on the extension gem