Update squizlabs/php_codesniffer requirement from ^3.10 to ^4.0

Updates the requirements on [squizlabs/php_codesniffer](https://github.com/PHPCSStandards/PHP_CodeSniffer) to permit the latest version.
- [Release notes](https://github.com/PHPCSStandards/PHP_CodeSniffer/releases)
- [Changelog](https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/4.x/CHANGELOG-4.x.md)
- [Commits](PHPCSStandards/PHP_CodeSniffer@3.10.0...4.0.0)

---
updated-dependencies:
- dependency-name: squizlabs/php_codesniffer
  dependency-version: 4.0.0
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

composer.json

@@ -68,7 +68,7 @@
         "phpunit/phpunit": "^9.6 || ^10 || ^11 || ^12",
         "slim/http": "^1.3",
         "slim/psr7": "^1.6",
-        "squizlabs/php_codesniffer": "^3.10",
+        "squizlabs/php_codesniffer": "^4.0",
         "vimeo/psalm": "^5 || ^6"
     },
     "autoload": {