For the following configuration
```
containerd_insecure_registries:
docker.io:
- dockerhubcache.example.com
```
the rendered /etc/containerd/config.toml contains
```
[plugins."io.containerd.grpc.v1.cri".registry.configs."docker.io".tls]
insecure_skip_verify = true
```
but it needs to be
```
[plugins."io.containerd.grpc.v1.cri".registry.configs."dockerhubcache.example.com".tls]
insecure_skip_verify = true
```