docs(nodejs): add docs about pnpm support

[mycodeself]

Description

This PR completes the PR #2414 adding references to the support of pnpm in the documentation.

I think this is all that is needed to reflect pnpm support, if I should update something else in the documentation let me know.

Related PRs

• feat(nodejs): add pnpm support #2414

Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

[knqyf263]

Thank you so much!