Add option to PowerShell

## Description

Add an option to set environment variables using PowerShell.

### Idea

Use the flag `--is-powershell` or `is-ps`.

## Reference

- [about_Environment_Variables](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_environment_variables?view=powershell-7.1)