update interpolate function in bruno js

[lohxt1]

Description

this is an extension of the pr #2234

~ updated the current interpolateString function in bruno-js to use the recursive interpolation function ~ added the processEnvVars to the assert runtime context

Contribution Checklist:

• [x] The pull request only addresses one issue or adds one feature.
• [ ] The pull request does not introduce any breaking changes
• [ ] I have added screenshots or gifs to help explain the change if applicable.
• [x] I have read the contribution guidelines.
• [x] Create an issue and link to the pull request.

[Its-treason]

Can the handlebars package be removed? I think you deleted all the handlebar Imports.

[helloanoop]

Merged. Thanks @lohxt1 !

Thanks for the review comments @Its-treason ! I have gone ahead and merged the PR. Please let us know if you had any additional comments on this and we will take it up in a follow-up PR