Support nested folder structure by API endpoint when import OpenAPI

[keidarcy]

Currently, insomnia supports one level structured folder by OpenAPI tags.
However, it would be nicer to support deep folder structure just by api string it self.

• /products
• /products/id
• /admin/products
• /admin/products/id

│── products
|     └── index
|     └── id
│── admin
|      └── products
|                └── index
|                └── id

simply, something like this:)