asdf toolversions does not seem to work with npm

[sdellis]

Introduction

Explain the goals and purpose of this documentation.
asdf install should install all the versions in the .tool-versions file. The npm version specified in tool-versions does not install. It says that npm plugin is not installed. There doesn't appear to be an npm plugin. This does not block development, but it would be helpful to have some documentation on this since asdf use of tool-versions is common practice among our developers.

Acceptance criteria

• If there is no docs directory, create one.

• Update an existing markdown document or add a new one in the docs directory.

• It has introduction: Explains the goals and purpose of this documentation.

• It has a step by step guide: Provides the exact steps to guide the user on how to do a task.

Additional acceptance criteria

• It includes references: References any related resources that have assisted creating this documentation (links to other tickets, online articles etc.).

• It includes workflow: Defines the steps in different environments (production, staging)