Bump phpro/grumphp-shim from 1.16.0 to 2.9.0

Bumps [phpro/grumphp-shim](https://github.com/phpro/grumphp-shim) from 1.16.0 to 2.9.0.
- [Release notes](https://github.com/phpro/grumphp-shim/releases)
- [Commits](phpro/grumphp-shim@v1.16.0...v2.9.0)

---
updated-dependencies:
- dependency-name: phpro/grumphp-shim
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

composer.json

@@ -21,7 +21,7 @@
     },
     "require-dev": {
         "phpstan/phpstan": "^1.10",
-        "phpro/grumphp-shim": "^1.5",
+        "phpro/grumphp-shim": "^2.9",
         "squizlabs/php_codesniffer": "^3.7",
         "thecodingmachine/phpstan-safe-rule": "^1.2",
         "phpstan/extension-installer": "^1.3",