[TASK] Update phpstan/phpstan requirement from ^1.12.3 to ^1.12.4 (#1466)

Updates the requirements on [phpstan/phpstan](https://github.com/phpstan/phpstan) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Changelog](https://github.com/phpstan/phpstan/blob/2.0.x/CHANGELOG.md)
- [Commits](https://github.com/phpstan/phpstan/compare/1.12.3...1.12.4)

---
updated-dependencies:
- dependency-name: phpstan/phpstan
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

composer.json

@@ -54,7 +54,7 @@
 		"php-parallel-lint/php-parallel-lint": "^1.4",
 		"phpmd/phpmd": "^2.15.0",
 		"phpstan/extension-installer": "^1.4.3",
-		"phpstan/phpstan": "^1.12.3",
+		"phpstan/phpstan": "^1.12.4",
 		"phpstan/phpstan-phpunit": "^1.4.0",
 		"phpstan/phpstan-strict-rules": "^1.6.0",
 		"phpunit/phpunit": "^9.6.20",