Extend tc interface to provide variable substitution function.

[moremo]

Please describe feature/problem details and solution you'd like.
Provide tc interface to substitute all variable text with values from environment similar to the Postman pm.environment.values.substitute function for Prerequest scripts.

Describe alternatives you've considered
Adding known env var substitutions to Prerequest scripts, which isn't very reusable and gets a bit unwieldy.

Your Team Size Using TC:
10

[rangav]

Thanks @moremo for the feedback, Will add to roadmap.