Support code spell checking

Problem/Motivation

Follow up #2972224: Add .cspell.json to automate spellchecking in Drupal core → , cspell, A Spell Checker for Code, is introduced to avoid misspelling in core.

It is an NPM package, but it's fine having it installed globally.

npm -g install cspell

See the change record for more See https://www.drupal.org/node/3122084 →

Proposed resolution

Add a step:cspell to validate_codebase.

Remaining tasks

Needs discussion

User interface changes

API changes

Data model changes

Release notes snippet