build(deps-dev): update phpstan/phpstan requirement

Updates the requirements on [phpstan/phpstan](https://github.com/phpstan/phpstan) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Commits](phpstan/phpstan@0.12.40...0.12.42)

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

composer.json

@@ -23,7 +23,7 @@
 		"nette/finder": "~2.5",
 		"nette/neon": "~3.0",
 		"phpstan/extension-installer": "1.0.5",
-		"phpstan/phpstan": "0.12.40",
+		"phpstan/phpstan": "0.12.42",
 		"phpstan/phpstan-deprecation-rules": "0.12.5",
 		"phpstan/phpstan-strict-rules": "0.12.5",
 		"symfony/config": "~4.4 || ~5.0",