Update phpstan/phpstan-strict-rules requirement from ^0.12.5 to ^0.12.9

Updates the requirements on [phpstan/phpstan-strict-rules](https://github.com/phpstan/phpstan-strict-rules) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan-strict-rules/releases)
- [Commits](phpstan/phpstan-strict-rules@0.12.5...0.12.9)

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

composer.json

@@ -22,7 +22,7 @@
     "require-dev": {
         "nette/tester": "^2.3.4",
         "phpstan/phpstan": "^0.12.56",
-        "phpstan/phpstan-strict-rules": "^0.12.5",
+        "phpstan/phpstan-strict-rules": "^0.12.9",
         "pepakriz/phpstan-exception-rules": "^0.11.2",
         "phpstan/phpstan-nette": "^0.12.10",
         "nepada/phpstan-nette-tester": "^0.3.1",