Support tgenv

[yutaro1985]

Hi,

I'd like to add tgenv support for Terragrunt.

Following is a quote from README of Terragrunt.

Terragrunt is a thin wrapper for Terraform that provides extra tools for keeping your Terraform configurations DRY, working with multiple Terraform modules, and managing remote state.

As mentioned in README, tgenv is inspired by tfenv, and has similar options to tfenv.

[kvendingoldo]

Hi ,
Try to use https://github.com/tofuutils/tenv to manage versions; It's a manager for Terraform/OpenTofu/Terragrunt/Atmos/Terramate written in Go.