[DeadCode] Skip with first class callable on RemoveUnusedPrivateMethodParameterRector (#7104)

Author: samsonasik

rules-tests/DeadCode/Rector/ClassMethod/RemoveUnusedPrivateMethodParameterRector/Fixture/do_not_remove_first_class_callable_param.php.inc

@@ -0,0 +1,16 @@
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\ClassMethod\RemoveUnusedPrivateMethodParameterRector\Fixture;
+
+final class SkipWithFirstClassCallable
+{
+    public function run()
+    {
+        return $this->validate(...);
+    }
+
+    private function validate(string $attribute, mixed $value): bool
+    {
+        return $value === true;
+    }
+}

rules-tests/DeadCode/Rector/ClassMethod/RemoveUnusedPrivateMethodParameterRector/Fixture/skip_with_first_class_callable.php.inc

@@ -199,10 +199,6 @@ private function resolveCallers(ClassMethod $classMethod, string $methodName, Ob
                 return false;
             }
 
-            if ($subNode->isFirstClassCallable()) {
-                return false;
-            }
-
             $nodeToCheck = $subNode instanceof MethodCall
                 ? $subNode->var
                 : $subNode->class;