🚀 Feature Request: Deleting a worker using `custom_domain`, does not delete the edge certificate generated for it

### Describe the solution

I noticed that when we use `custom_domain = true`, a new edge certificate is created for that custom domain. Deleting the worker does not delete that advanced certificate. We are using this for review apps, and so we have lots of custom domains, and this leads to lots of certificates being built up.

未指定文件或测试。首先跟踪使用 custom_domain = true 的 worker 的删除流程，然后继续了解关联的 edge 证书是如何创建和管理的。完成标准是删除 worker 的同时也会删除其生成的证书，且不会影响不相关的证书。

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