Just updating to say you can get the packaged workflow from the releases link. https://github.com/darrenpmeyer/alfred-litra/releases
For anyone else searching this, to get hidapitester to open I had to right click on the workflow name in the list of workflows and select "Open in Finder" then command right click hidapitester, select open, and approve. Then it stops throwing an error. (I don't know if you need Xcode command line tools to run this instance of hidapitester but I had it already). However I still can't get the workflow to work.... wish there was some documentation about how to use it.