Merge pull request #1013 from cakephp/php-8.4

Run testsuite on PHP 8.4

Author: othercorey

.github/workflows/ci.yml

@@ -25,6 +25,9 @@ jobs:
         include:
           - php-version: '8.1'
             dependencies: 'lowest'
+          - php-version: '8.4'
+            dependencies: 'highest'
+            composer-options: '--ignore-platform-req=php'
 
     steps:
     - uses: actions/checkout@v4
@@ -64,7 +67,7 @@ jobs:
         php-version: '8.1'
         extensions: mbstring, intl
         coverage: none
-        tools: cs2pr, phpstan:1.10
+        tools: cs2pr, phpstan:1.12
 
     - name: Composer install
       uses: ramsey/composer-install@v3