Drop PHP 8.4 from CI matrix, CakePHP 4.x dependencies do not support it

Author: arusinowski

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php-version: ['8.1', '8.2', '8.3', '8.4']
+        php-version: ['8.1', '8.2', '8.3']
         db-type: [sqlite, mysql, pgsql]
         prefer-lowest: ['']