Add composer requirements

Author: ioigoume

composer.json

@@ -31,7 +31,9 @@
         "psr/log": "^3.0",
         "slevomat/coding-standard": "^8.20",
         "squizlabs/php_codesniffer": "^3.13 || ^4.0",
-        "symfony/phpunit-bridge": "^7.3 || ^8.0"
+        "symfony/phpunit-bridge": "^7.3 || ^8.0",
+        "maglnet/composer-require-checker": "^4",
+        "icanhazstring/composer-unused": "^0.9"
     },
     "require-dev": {
         "simplesamlphp/simplesamlphp": "^2.4"