Build/Test Tools: Remove `check-latest` input for `setup-node`.

The `check-latest` setting is used to ensure the latest version of Node.js is always installed in GitHub Action workflows.

This input was added and turned on in [57212] when the minimum required version of Node.js was bumped to `20.10.0`. Because GitHub Action runner image updates are deployed on a rolling basis over the course of several days, a version of Node.js that met this new requirement was not always present (especially on Windows runners). Using this input was a temporary fix to ensure stability for Core’s test workflows. 

The `check-latest` input does have some side effects. Two examples are:
- An additional request is performed to check the latest version every time `setup-node` is used with this option enabled. More requests are made to download and install a newer version of Node.js when one is available.
- When new versions of Node.js are released, the Core workflows immediately switch to the new version, which could potentially have undiscovered bugs or regressions.

The latter has surfaced today due to a regression in Node.js 20.13.0 on Windows (see https://github.com/nodejs/node/issues/52884).

A bit of time has passed and a version >=20.10.0 is now reliably available on all GitHub Action runners. Running the very latest release Node.js is also not important for Core’s testing setup, so `check-version` can safely be removed to address both side effects detailed above. 

Props johnbillion.
Fixes #60129.
Built from https://develop.svn.wordpress.org/trunk@58120


git-svn-id: http://core.svn.wordpress.org/trunk@57585 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.6-alpha-58119';
+$wp_version = '6.6-alpha-58120';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.