feat: support .node-version file

[totto2727]

SEMVER Update Type:

• [x] Major
• [ ] Minor
• [ ] Patch

Description:

support .node-version file

Motivation:

Most Node.js runtime managers support either .nvmrc or .node-version (nodenv etc...) or both (fnm, mise, asdf etc...) are supported.

However, currently only .nvmrc is supported.

Although it is preferable to use .nvmrc since we use nvm internally, both .nvmrc and .node-version are often in the same format.

It is possible that I am missing a specification, but I don't think it will be a problem in many cases.

Test

https://app.circleci.com/pipelines/github/totto2727/node-orb

Checklist:

• [ ] All new jobs, commands, executors, parameters have descriptions.
• [ ] Usage Example version numbers have been updated.
• [ ] Changelog has been updated.