Feat: Update the Plans API to be able to fetch & return resource changes

[AhmedRaafat14]

Description

This adds a new function to the Plans API (ReadResourceChanges) that takes a PlanID and return a list of all resource changes done by the target plan.

Testing plan

External links

Output from tests

[hashicorp-cla]

All committers have signed the CLA.

[brandonc]

Hey, @AhmedRaafat14, thanks for the contribution. Unfortunately, we've made a conscious decision not to include this endpoint in our public API in order to reserve the right to change it or break it in the future. Including it here would link it to the stability guarantees implied by the go-tfe version. Furthermore, the profuse interface{} types limit the utility of the public types anyway.

I don't discourage you from using this endpoint! I would just try to isolate it in your code as "internal HashiCorp API that isn't covered by their stability policy"

[AhmedRaafat14]

Hi @brandonc thanks for your reply and these information.