ci(deps): update GitHub actions to run on Node.js 20 (LTS)

[MikeMcC399]

This PR bumps

• .nvmrc from Node.js 14, which reached end-of-life on Apr 30, 2023, to Node.js 20, which is the current Long Term Support (LTS) version, announced as Node.js v20.9.0 on Oct 24, 2023.

Also in GitHub Actions workflows

• main.yml
• publish-on-tag.yml

the following GitHub Action are bumped

• actions/checkout to actions/checkout@v4
• actions/setup-node to actions/setup-node@v4

to resolve the GitHub Actions deprecation warning:

Node.js 12 actions are deprecated. Please update the following actions to use Node.js 16: actions/checkout@v2. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/.

and the planned deprecation of node16 (see blog post GitHub Actions: Transitioning from Node 16 to Node 20 Sep 22, 2023).

[MikeMcC399]

• I successfully tested this as far as I could in https://github.com/MikeMcC399/punycode.js/actions
• This PR was motivated by the recent introduction of a runtime deprecation notice for the Node.js version of punycode in the Node.js 21.x current release, which is certain to increase the interest and visibility into this repo!

Further details

DEP0040 in the History section of the Node.js documentation shows that Node.js punycode has been deprecated since Node.js v7.0.0 and, starting with Node.js v21.0.0, this has been changed to a runtime deprecation (see nodejs/node#47202). The runtime deprecation is causing it to now become visible.

Node.js v21.0.0 was released on Oct 17, 2023 as the first release of the 21.x major version, so the issue is quite new.

Typically the deprecation notice looks like this:

(node:2136) [DEP0040] DeprecationWarning: The punycode module is deprecated. Please use a userland alternative instead.
(Use node --trace-deprecation ... to show where the warning was created)

and I'm seeing this appearing in many places, including when Yarn Classic is used to add a package.

[mathiasbynens]

Thanks!

[MikeMcC399]

@mathiasbynens

You're very welcome!