Raise requirements to PHP 8.3, update dependencies

Author: Hackwar

composer.json

@@ -6,13 +6,13 @@
     "homepage": "https://github.com/joomla-framework/github-api",
     "license": "GPL-2.0-or-later",
     "require": {
-        "php": "^8.1.0",
-        "joomla/http": "^3.0",
-        "joomla/registry": "^3.0",
-        "joomla/uri": "^3.0"
+        "php": "^8.3.0",
+        "joomla/http": "dev-4.x-dev",
+        "joomla/registry": "dev-4.x-dev",
+        "joomla/uri": "dev-4.x-dev"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.5.28",
+        "phpunit/phpunit": "^12.2.7",
         "squizlabs/php_codesniffer": "^3.7.2",
         "phpstan/phpstan": "^2.1.17",
         "phpstan/phpstan-deprecation-rules": "^2.0.3"
@@ -31,7 +31,8 @@
     "extra": {
         "branch-alias": {
             "dev-2.0-dev": "2.0-dev",
-            "dev-3.x-dev": "3.0-dev"
+            "dev-3.x-dev": "3.0-dev",
+            "dev-4.x-dev": "4.0-dev"
         }
     }
 }