[Feature Request] Support Path variables

[KyleKorndoerfer]

a feature from Postman that I use regularly and is preventing more use of Nightingale is support for Path variables. This is an old but still accurate description of how it works for anyone unfamiliar: http://makeseleniumeasy.com/2019/08/07/postman-tutorial-part-31-uri-path-variables-in-postman/

No, this is not something that can be accomplished with chaining as there isn't a previous request that would set the value for this call in many of the use cases I have that would benefit from this ability.