feat!: ESLint 9 Fixes (#307)

* chore: update postinstall scripts
* chore(lint): eslint automated fixes
* feat!: drop standard, sonarjs to work with eslint9

- This config allows arrow functions.

BREAKING CHANGES:

- Switches to eslint-config-eslint from eslint-config-standard.
- Also drops eslint-plugins-sonarjs because it doesn't work well
  with eslint9, and wants eslint8 and related plugins.
- Switches from eslint-plugin-prettier to eslint-config-prettier.

packages/config-checker/__tests__/config-checker.test.js

@@ -1,19 +1,18 @@
-'use strict'
+/* eslint no-console: "off" -- CLI app that gives users feedback */
 
-const path = require('path')
+const path = require('node:path')
 const configChecker = require('..')
-const assert = require('assert').strict
+const assert = require('node:assert').strict
 
 const configs = configChecker('test', path.join(__dirname, 'fixtures'))
 
 /**
  * Checks if an array contains a file.
- *
- * @param {string[]} configs - The array of configs to check.
- * @param {string} file - The file to check for.
+ * @param {string[]} c The array of configs to check.
+ * @param {string} file The file to check for.
  * @returns {boolean} - True if the array contains the file.
  */
-const arrayContains = (configs = [], file = '') => configs.some(config => config === file)
+const arrayContains = (c = [], file = '') => c.includes(file)
 
 assert.ok(arrayContains(configs, '.testrc'))
 assert.ok(arrayContains(configs, '.config/testrc.ts'))