If loading the workflow definition takes time, the Workflow Editor is blank, and this causes confusion and not clear whats happening

Root cause in code:
WorkflowEditor component doesn't pass the pending property to PromiseStateWrapper while loading the data

https://github.com/caponetto/backstage-plugins/blob/KOGITO-9778-setup/plugins/orchestrator/src/components/WorkflowEditor/WorkflowEditor.tsx#L423