【报Bug】iOS平台打开带有图片列表的小程序，关闭之后可能会出现闪退

操作步骤：

 DCUniMPMenuActionSheetItem *item1 = [[DCUniMPMenuActionSheetItem alloc] initWithTitle:@"重启" identifier:@"item1"]  
    // 添加到全局配置  
    [DCUniMPSDKEngine setDefaultMenuItems:@[]];  

    // 设置 delegate  
    [DCUniMPSDKEngine setDelegate:self];  

    // 启动 uni小程序，（参数可以在小程序中通过 plus.runtime.arguments 获取此参数）  
    NSMutableDictionary *arguments = [NSMutableDictionary dictionary];  

    DCUniMPConfiguration *config = [DCUniMPConfiguration new];  
    config.arguments = arguments;  
    config.redirectPath = self.uniAppPath;  
    self.uniAppPath = nil;  
     config.enableBackground = NO;  

    [DCUniMPSDKEngine preloadUniMP:packName configuration:config completed:^(DCUniMPInstance * _Nullable uniMPInstance, NSError * _Nullable error) {  
         if (uniMPInstance) {  
             // 预加载后打开小程序  
             [uniMPInstance showWithCompletion:^(BOOL success, NSError * _Nullable error) {  

                 if (error) {  
                     NSLog(@"show 小程序失败：%@",error);  
                     TOASTOFSTRING(kQMLocalStr(@"打开小程序失败"));  
                 }  
             }];  
         } else {  
              [self.topController.view hideToastActivity];  
             NSLog(@"预加载小程序出错：%@",error);  
         }  
     }];  

/// 小程序关闭回调方法

• (void)uniMPOnClose:(NSString *)appid {
  self.uniMpInstance = nil;
  NSLog(@"小程序 %@ 被关闭了",appid);
  }

预期结果：

关掉小程序，app不会闪退

实际结果：

-[H5CoreImageLoader callDelegate:Image:type:userInfo:] + 64
2 CoreFoundation 0x000000018f2fe000 + 645152
3 CoreFoundation 0x000000018f2fe000 + 8556
[H5CoreImageLoaderReq enumerateObjectsUsingBlock:] + 80
[H5CoreImageLoader loadImage:withDelegate:withContext:]_block_invoke_2.173 + 180
[PDRCore runInMainThread:]_block_invoke + 36