Cant be used with non-yarn package managers and when yarn is also installed #792

Describe the bug
Cant be used in projects using other package managers other than yarn and when yarn is also installed

To Reproduce
Steps to reproduce the behavior:

• (optional): npm install yarn -g
• mkdir bug && cd bug
• pnpm init
• pnpm add postman-code-generators

Expected code snippet and corresponding request
work

Screenshots

Additional context
#792