chore: composer require --dev phpstan/phpstan-strict-rules

Author: kenjis

composer.json

@@ -27,6 +27,7 @@
         "nexusphp/tachycardia": "^1.0",
         "php-coveralls/php-coveralls": "^2.5",
         "phpstan/phpstan": "^1.10.2",
+        "phpstan/phpstan-strict-rules": "^1.5",
         "phpunit/phpcov": "^8.2",
         "phpunit/phpunit": "^9.1",
         "predis/predis": "^1.1 || ^2.0",