Hi there,
What type of data or action are you trying to get from Aria Automation via an Orchestrator workflow?
Since the article was published, the 'Aria Automation Orchestrator Plug-in' has added more built in Infrastructure objects - it contains many objects and in-built methods you can used to get information from Aria Automation or execute updates. The below screen shot is from my Home Lab:

If this doesn't give you what you need, as the article states, you can also use the generic REST operation Workflows in the Library to 'Get' 'Patch' 'Post' 'Put' against your Aria Automation Plug-In endpoint, or you can wrap the Workflows in your own Workflow. I would recommend doing this first to get going rather than unpacking the workflow code and writing your own REST API code as these are pre-built and ready to go to perform REST operations.

Here is an example of a quick execution that for the Uri path you mentioned to get Deployments:

An excerpt of the result n the Workflow execution log:

I hope that helps.
Regards,
Greg D, VMware