添加 _UIAlertControllerTextField 到白名单，以修复 UIAlertViewController 添加 TextField 文本输入框时的误报。

[TinyQ]

当在执行下面后，关闭弹出的 Alert ，会报内存泄漏。
代码如下：

    UIAlertController *alter = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert];
    UIAlertAction *sure = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
    }];
    UIAlertAction *cancle = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil];
    UIAlertAction *delete = [UIAlertAction actionWithTitle:@"删除" style:UIAlertActionStyleDestructive handler:nil];
    [alter addTextFieldWithConfigurationHandler:^(UITextField * _Nonnull textField) {
    }];
    [alter addAction:sure];
    [alter addAction:cancle];
    [alter addAction:delete];
    [self presentViewController:alter animated:YES completion:^{
        
    }];

泄漏提示：

2018-01-31 16:58:53.940825+0800 Demo[78899:4176582] Possibly Memory Leak.
In case that _UIAlertControllerTextField should not be dealloced, override -willDealloc in _UIAlertControllerTextField by returning NO.
View-ViewController stack: (
    UIAlertController,
    "_UIAlertControllerView",
    UIView,
    "_UIAlertControllerInterfaceActionGroupView",
    UIView,
    "_UIInterfaceActionGroupHeaderScrollView",
    UIView,
    UIView,
    UICollectionViewControllerWrapperView,
    UICollectionView,
    "_UIAlertControllerTextFieldViewCollectionCell",
    UIView,
    "_UIAlertControllerTextFieldView",
    UIView,
    UIView,
    "_UIAlertControllerTextField"
)

[cddjr]

16年的pr #28 已经作出了类似调整，但一直没被合并