Update dependency phpunit/phpunit to v12

| datasource | package         | from    | to     |
| ---------- | --------------- | ------- | ------ |
| packagist  | phpunit/phpunit | 11.5.17 | 12.1.2 |


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

Author: renovate[bot]

composer.json

@@ -31,7 +31,7 @@
     "patchlevel/coding-standard": "^1.3.0",
     "phpbench/phpbench": "^1.2.15",
     "phpstan/phpstan": "^2.1.0",
-    "phpunit/phpunit": "^11.5.17",
+    "phpunit/phpunit": "^12.0.0",
     "psalm/plugin-phpunit": "^0.19.2",
     "roave/infection-static-analysis-plugin": "^1.36.0",
     "symfony/var-dumper": "^5.4.29 || ^6.4.0 || ^7.0.0",