[4.5] fix: spark does not work with composer install --no-dev

[kenjis]

Description
Follow-up #8388

$ composer install --no-dev
$ ./spark

[Error]
Class "PHPUnit\Framework\TestCase" not found
at SYSTEMPATH/Test/CIUnitTestCase.php:40

Backtrace:
  1    VENDORPATH/composer/ClassLoader.php:576
       include()

  2    VENDORPATH/composer/ClassLoader.php:427
       Composer\Autoload\{closure}('/Users/kenji/work/codeigniter/official/CodeIgniter4-4.5/vendor/composer/../../system/Test/CIUnitTestCase.php')

  3    ROOTPATH/tests/system/Commands/BaseCommandTest.php:26
       Composer\Autoload\ClassLoader()->loadClass('CodeIgniter\\Test\\CIUnitTestCase')

  4    SYSTEMPATH/Autoloader/Autoloader.php:310
       include_once('/Users/kenji/work/codeigniter/official/CodeIgniter4-4.5/tests/system/Commands/BaseCommandTest.php')

  5    SYSTEMPATH/Autoloader/Autoloader.php:289
       CodeIgniter\Autoloader\Autoloader()->includeFile('/Users/kenji/work/codeigniter/official/CodeIgniter4-4.5/tests/system/Commands/BaseCommandTest.php')

  6    SYSTEMPATH/Autoloader/Autoloader.php:267
       CodeIgniter\Autoloader\Autoloader()->loadInNamespace('Tests\\system\\Commands\\BaseCommandTest')

  7    [internal function]
       CodeIgniter\Autoloader\Autoloader()->loadClass('Tests\\system\\Commands\\BaseCommandTest')

  8    SYSTEMPATH/Autoloader/FileLocator.php:296
       class_exists('Tests\\system\\Commands\\BaseCommandTest')

  9    SYSTEMPATH/CLI/Commands.php:112
       CodeIgniter\Autoloader\FileLocator()->findQualifiedNameFromPath('/Users/kenji/work/codeigniter/official/CodeIgniter4-4.5/tests/system/Commands/BaseCommandTest.php')

 10    SYSTEMPATH/CLI/Commands.php:49
       CodeIgniter\CLI\Commands()->discoverCommands()

 11    SYSTEMPATH/Config/Services.php:176
       CodeIgniter\CLI\Commands()->__construct()

 12    SYSTEMPATH/Config/BaseService.php:261
       CodeIgniter\Config\Services::commands(false)

 13    SYSTEMPATH/Config/BaseService.php:202
       CodeIgniter\Config\BaseService::__callStatic('commands', [...])

 14    SYSTEMPATH/Config/Services.php:173
       CodeIgniter\Config\BaseService::getSharedInstance('commands')

 15    SYSTEMPATH/Config/BaseService.php:261
       CodeIgniter\Config\Services::commands()

 16    SYSTEMPATH/CLI/Console.php:43
       CodeIgniter\Config\BaseService::__callStatic('commands', [])

 17    ROOTPATH/spark:102
       CodeIgniter\CLI\Console()->run()

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