Require php8.3+ (fix #7)

Author: o0h

composer.json

@@ -3,10 +3,9 @@
     "type": "library",
     "description": "AST-based PHP source diff checker",
     "require": {
-        "php": ">8.2",
+        "php": "~8.3.0",
         "nikic/php-parser": "^4.16",
-        "symfony/console": "^6.3",
-        "symfony/polyfill-php83": "@stable"
+        "symfony/console": "^6.3"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "@stable",