Update dependency orchestra/testbench to v9

| datasource | package             | from   | to    |
| ---------- | ------------------- | ------ | ----- |
| packagist  | orchestra/testbench | 8.22.0 | 9.0.0 |


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

Author: renovate[bot]

composer.json

@@ -15,7 +15,7 @@
     },
     "require-dev": {
         "interaction-design-foundation/coding-standard": "^0.2.0",
-        "orchestra/testbench": "^8.3",
+        "orchestra/testbench": "^9.0",
         "phpunit/phpunit": "^10.5 || ^11.0",
         "vimeo/psalm": "^5.22"
     },