Issue with Global Defined Variables in httpbook

[kscarr73]

I have an http file that I am using in httpbook.

I am trying to use the testing variable in a POST call.

/*
# Testing

Validate some calls
*/
@testing = this
###

GET {{defaultUrl}}/records/
###

POST {{defaultUrl}}/records

{
    "testing": "{{testing}}"
}

If I run in the Text Editor, the call works without problem. If I run the cell in httpbook, it claims the testing variable doesn't exist.