refactor: replace config(Paths::class)

[kenjis]

Description
Paths is immutable, so we do not need to share the instance.
And config(Paths::class) is slower than new Paths().

Test	Time	Memory
new paths()	0.0023	0 Bytes
config(paths::class)	0.0182	0 Bytes

<?php

namespace App\Controllers;

use Config\Paths;

class Home extends BaseController
{
    public function index()
    {
        $iterator = new \CodeIgniter\Debug\Iterator();

        $iterator->add('new Paths()', static function () {
            $config = new Paths();
        });

        $iterator->add('config(Paths::class)', static function () {
            $config = config(Paths::class);
        });

        return $iterator->run(10000);
    }
}

Related #7696

Checklist:

• Securely signed commits
• [] Component(s) with PHPDoc blocks, only if necessary or adds value
• [] Unit testing, with >80% coverage
• [] User guide updated
• Conforms to style guide