Updated dependencies

Author: kukulich

composer.json

@@ -14,7 +14,7 @@
 	"require-dev": {
 		"jakub-onderka/php-parallel-lint": "0.9.2",
 		"phing/phing": "2.16",
-		"phpstan/phpstan": "0.8.0",
+		"phpstan/phpstan": "0.8.3",
 		"phpunit/phpunit": "6.3.0"
 	},
 	"autoload": {