Adding CA certificate into Coder template failing build (k8s)

Using the [devcontainer Coder template](https://github.com/coder/coder/blob/main/examples/templates/kubernetes-devcontainer/main.tf) I'm seeing the following issue when mounting my CA certificates:

```bash
error: temp remount: temp remount: bind mount /ca-certs/ca-file => /.envbuilder/mnt/ca-certs/ca-file: permission denied
```

Adding certificate directory to ENV:
```hcl

locals {
...
"SSL_CERT_DIR" : "/ca-certs"
//or
"SSL_CERT_FILE": "/ca-certs/ca-file"
}
```

```hcl
resource "kubernetes_deployment" "main" {
...

spec {
template {
spec {
...
volume_mount {
name = "ca-file"
mount_path = "/ca-certs/ca-file"
}
}

volume {
name = "ca-file"
secret {
secret_name = "coder-tls"
}
...
}
}
```

Just trying to have the container built trust my private PKI services.

Start with examples/templates/kubernetes-devcontainer/main.tf and reproduce the CA certificate mount in Kubernetes using the reported configuration. Trace the environment builder's handling of the /ca-certs/ca-file bind mount and verify that a build can trust the private PKI without the permission-denied remount error.

Written by the indexing model from the issue text.