Update phpmd/phpmd requirement from ^2.13 to ^2.14

Updates the requirements on [phpmd/phpmd](https://github.com/phpmd/phpmd) to permit the latest version.
- [Release notes](https://github.com/phpmd/phpmd/releases)
- [Changelog](https://github.com/phpmd/phpmd/blob/master/CHANGELOG)
- [Commits](phpmd/phpmd@2.13.0...2.14.1)

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

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

composer.json

@@ -35,7 +35,7 @@
     "juliangut/phpstan-config": "^1.1",
     "overtrue/phplint": "^9.0",
     "phpcompatibility/php-compatibility": "^9.3",
-    "phpmd/phpmd": "^2.13",
+    "phpmd/phpmd": "^2.14",
     "povils/phpmnd": "^3.2",
     "roave/security-advisories": "dev-master"
   },