Add support for cache type bun

[koozz]

Description:
The setup-node action is a popular tool for setting up Node.js environments in GitHub Actions workflows. Currently, it supports npm, pnpm, and yarn as package managers. However, there’s a need to include support for Bun, a faster JavaScript runner.

Justification:
Bun offers performance improvements over traditional JavaScript runners, making it an attractive choice for developers. By adding support for Bun in the setup-node action, GitHub Actions workflows can benefit from its speed and efficiency.

Are you willing to submit a PR?
I will have a look.

[aparnajyothi-y]

Hello @koozz, Thank you for creating this feature request and we will get back to you once we have some feedback on this :)

[silverwind]

I think such a cache should likely be part of https://github.com/oven-sh/setup-bun.

[koozz]

I reckon this action should cache all node dependencies, right? Since we run this after setup-node or setup-bun, whether we use npm, pnpm, yarn or bun. It felt the like the right place where this action does 1 thing and does it well (with a post step to store the cache).