Fixing PHPStan rule

Author: moufmouf

composer.json

@@ -15,9 +15,9 @@
         "thecodingmachine/safe": "^0.1.11"
     },
     "require-dev": {
-        "phpunit/phpunit": "^7.1",
+        "phpunit/phpunit": "^7.5.2",
         "php-coveralls/php-coveralls": "^2.1",
-        "squizlabs/php_codesniffer": "^3.2"
+        "squizlabs/php_codesniffer": "^3.4"
     },
     "autoload": {
         "psr-4": {