Add cake-module tag to Cake.UrlLoadDirective.Module NuGet package

The NuGet Gallery will soon include a "Cake" tab with instructions on how to use NuGet packages in Cake build scripts. I'd like to suggest that you include the tag `cake-module` in the NuGet package of this module, so that the NuGet Gallery can display the correct instructions to install this module.

The UI will look similar to this:


Documentation on best practices on tags for Cake modules: https://cakebuild.net/docs/extending/modules/best-practices#tags

首先找到 Cake.UrlLoadDirective.Module 的 NuGet 包元数据，并查看链接的 Cake 模块标签最佳实践文档。将 cake-module 标签添加到包元数据中，然后验证生成的 NuGet 包包含该标签。

由索引模型根据 Issue 内容生成。