feat: Add built-in PostgreSQL for simple production setup (#2345)

* feat: Add built-in PostgreSQL for simple production setup

Fixes #2321.

* Use fork of embedded-postgres for cache path

examples/templates/kubernetes-multi-service/main.tf

@@ -21,9 +21,7 @@ variable "use_kubeconfig" {
   Kubernetes cluster as you are deploying workspaces to.
 
   Set this to true if the Coder host is running outside the Kubernetes cluster
-  for workspaces.  A valid "~/.kube/config" must be present on the Coder host. This
-  is likely not your local machine unless you are using `coder server --dev.`
-
+  for workspaces.  A valid "~/.kube/config" must be present on the Coder host.
   EOF
 }