Update phpstan/phpstan requirement from ~1.8.2 to ~1.9.0

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/1.9.x/CHANGELOG.md)
- [Commits](phpstan/phpstan@1.8.2...1.9.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

composer.json

@@ -23,7 +23,7 @@
     "php": "^7.2.0 || ^8.1.0",
     "ext-dom": "*",
     "laminas/laminas-code": "~3.3.0 || ~3.4.1 || ~3.5.1 || ~4.5.0 || ~4.5.2",
-    "phpstan/phpstan": "~1.8.2",
+    "phpstan/phpstan": "~1.9.0",
     "symfony/finder": "^3.0 || ^4.0 || ^5.0 || ^6.0"
   },
   "conflict": {