“The form cannot be displayed because session state is not available.” Error in SharePoint UI-Based Workflow Configuration

My client was seeing an odd error in one of their environments, bot not any of the others.  When you would go to configure an out-of-the-box workflow on a site, you’d see the "The form cannot be displayed because session state is not available." error after clicking Next on the first configuration screen (/_layouts/AddWrkfl.aspx). Some…