Update dependency phpstan/phpstan to v2

| datasource | package         | from  | to     |
| ---------- | --------------- | ----- | ------ |
| packagist  | phpstan/phpstan | 1.9.4 | 2.1.20 |


Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

composer.json

@@ -31,7 +31,7 @@
     "laminas/laminas-servicemanager": "^3.20",
     "patchlevel/coding-standard": "^1.2.0",
     "phpspec/prophecy-phpunit": "^2.0.1",
-    "phpstan/phpstan": "^1.8.2",
+    "phpstan/phpstan": "^2.0.0",
     "phpunit/phpunit": "^9.5.23",
     "psalm/plugin-phpunit": "^0.18.0",
     "roave/infection-static-analysis-plugin": "^1.22.0",