Collections imported from Postman use incorrect syntax for environment variables

### Expected Behavior

When I import a Postman collection into Insomnia, I would like it to work without any further modifications. Unfortunately, this is not possible since none of the variables can be resolved afterward.

### Actual Behavior

Postman uses the syntax `{{my-variable}}` to reference variables from the environment. This is imported into Insomnia as is but Insomnia would actually require `{{ _['my-variable'] }}` to correctly reference a variable from an environment in Insomnia.

The imported request:

Details about the variable using in the URL:

The way Insomnia can use the variable:

If I export the new Insomnia collection again, the JSON shows the two different syntax variants:
```json
{
"_type": "export",
"__export_format": 4,
"__export_date": "2023-07-27T05:42:24.205Z",
"__export_source": "insomnia.desktop.app:v2023.4.0",
"resources": [
{
"_id": "req_d14ba894132946e38504cc06db32ceb0",
"parentId": "fld_957c215ce3c54ecb956087081a47ecdb",
"modified": 1690436504823,
"created": 1690436253238,
"url": "{{ _['config-base-url'] }}/:applicationName/:profile",
"name": "Get Default Service Configuration",
"description": "",
"method": "GET",
"body": {},
"parameters": [],
"headers": [],
"authentication": {},
"metaSortKey": -1690436253238,
"isPrivate": false,
"settingStoreCookies": true,
"settingSendCookies": true,
"settingDisableRenderRequestBody": false,
"settingEncodeUrl": true,
"settingRebuildPath": true,
"settingFollowRedirects": "global",
"_type": "request"
},
...
{
"_id": "req_61ae16d74eda4caea60cc69a4e60712c",
"parentId": "fld_957c215ce3c54ecb956087081a47ecdb",
"modified": 1690436253238,
"created": 1690436253238,
"url": "{{config-base-url}}/:applicationName/:profile/:label",
"name": "Get Service Configuration with Label",
"description": "",
"method": "GET",
"body": {},
"parameters": [],
"headers": [],
"authentication": {},
"metaSortKey": -1690436253238,
"isPrivate": false,
"settingStoreCookies": true,
"settingSendCookies": true,
"settingDisableRenderRequestBody": false,
"settingEncodeUrl": true,
"settingRebuildPath": true,
"settingFollowRedirects": "global",
"_type": "request"
},
...
]
}
```

P.S.: Also note how Postman supported path parameters (variables in the path) like `:applicationName` and `:profile` which are not understood by Insomnia as such.

### Reproduction Steps

1. On the main screen, click on _+ Create_ and select _Import_
2. Choose the file of a previously exported Postman collection using environment variables
3. Click _Scan_
4. Click _Import_ on the next screen
5. Open the collection in the imported workspace

### Is there an existing issue for this?

- [X] I have searched the [issue tracker](https://www.github.com/Kong/insomnia/issues) for this problem.

### Additional Information

_No response_

### Insomnia Version

2023.4.0

### What operating system are you using?

macOS

### Operating System Version

Ventura 13.4.1

### Installation method

homebrew

### Last Known Working Insomnia version

_No response_

Reproduce the problem through the documented Create → Import → Scan → Import flow using a Postman collection with environment and path variables. Start by examining how the imported collection represents {{my-variable}} and :applicationName; done means imported environment variables resolve in requests and supported Postman path parameters work without manual edits.

Written by the indexing model from the issue text.