Move codeigniter4/framework to require-dev (#33)

* Move codeigniter4/framework to require-dev

To avoid dependabot error in CodeIgniter 4 repo, see https://github.com/codeigniter4/CodeIgniter4/network/updates/953278072

* add "codeigniter4/framework": "<4.5" to conflict

Author: samsonasik

composer.json

@@ -23,10 +23,10 @@
     },
     "require": {
         "php": "^8.1",
-        "codeigniter4/framework": "^4.5",
         "phpstan/phpstan": "^2.0"
     },
     "require-dev": {
+        "codeigniter4/framework": "^4.5",
         "codeigniter/coding-standard": "^1.7",
         "codeigniter4/shield": "^1.0",
         "friendsofphp/php-cs-fixer": "^3.49",
@@ -38,7 +38,8 @@
         "phpunit/phpunit": "^10.5 || ^11.4"
     },
     "conflict": {
-        "codeigniter/framework": "*"
+        "codeigniter/framework": "*",
+        "codeigniter4/framework": "<4.5"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,