Fatal error: Uncaught Error: Call to undefined function SilverStripe\Core\Manifest\json_decode() in /app/vendor/silverstripe/framework/src/Core/Manifest/Module.php:200 Stack trace: #0 /app/vendor/silverstripe/framework/src/Core/Manifest/Module.php(60): SilverStripe\Core\Manifest\Module->loadComposer() #1 /app/vendor/silverstripe/framework/src/includes/constants.php(213): SilverStripe\Core\Manifest\Module->__construct('/app', '/app') #2 /app/vendor/composer/autoload_real.php(73): require('/app/vendor/sil...') #3 /app/vendor/composer/autoload_real.php(63): composerRequirebffb9eb5bc294369427da250b962748e('795b01cf23ed94c...', '/app/vendor/com...') #4 /app/vendor/autoload.php(7): ComposerAutoloaderInitbffb9eb5bc294369427da250b962748e::getLoader() #5 /app/public/index.php(15): require('/app/vendor/aut...') #6 {main} thrown in /app/vendor/silverstripe/framework/src/Core/Manifest/Module.php on line 200