build: add test scripts

Author: g105b

composer.json

@@ -29,6 +29,19 @@
 		}
 	],
 
+	"scripts": {
+		"phpunit": "vendor/bin/phpunit --configuration phpunit.xml",
+		"phpstan": "vendor/bin/phpstan analyse --level 6 src --memory-limit 256M",
+		"phpcs": "vendor/bin/phpcs src --standard=phpcs.xml",
+		"phpmd": "vendor/bin/phpmd src/ text phpmd.xml",
+		"test": [
+			"@phpunit",
+			"@phpstan",
+			"@phpcs",
+			"@phpmd"
+		]
+	},
+
 	"autoload": {
 		"psr-4": {
 			"Gt\\TypeSafeGetter\\": "./src"