fix: Services::request() should call AppServices instead static

[pjsde]

CodeIgniter\Config\Services::request() should return Config\Services::incomingrequest() instead of static::incomingrequest() to allow override the IncomingRequest

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

[kenjis]

@pjsde Thank you!