chore: remove "NamedFilter(userProvided: true, string: php)"

::warning file=/home/runner/work/playground/playground/composer.json,line=0,col=0::"NamedFilter(userProvided: true, string: codeigniter4/framework)" exclusion is a zombie
Warning: "NamedFilter(userProvided: true, string: php)" exclusion is a zombie
Error: Process completed with exit code 1.

composer-unused.php

@@ -7,6 +7,5 @@
 
 return static function (Configuration $config): Configuration {
     return $config
-        ->addNamedFilter(NamedFilter::fromString('codeigniter4/framework'))
-        ->addNamedFilter(NamedFilter::fromString('php'));
+        ->addNamedFilter(NamedFilter::fromString('codeigniter4/framework'));
 };