fix: 修复 ObjectPropertyValidator 泛型类型定义

- 修改 `ObjectPropertyValidator` 构造函数中的泛型参数定义
- 将 `Function<T, TProperty>` 改为 `Function<T, ? extends TProperty>`
- 解决了泛型类型不匹配的问题，提高了类型安全性

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/ObjectPropertyValidator.java

@@ -28,7 +28,7 @@ import java.util.function.Function;
 public class ObjectPropertyValidator<T, TProperty>
         extends BasePropertyValidator<T, TProperty, ObjectPropertyValidator<T, TProperty>> {
 
-    ObjectPropertyValidator(Function<T, TProperty> getter) {
+    ObjectPropertyValidator(Function<T, ? extends TProperty> getter) {
         super(getter);
     }