chore(dotfiles): mention that setting the `dotfiles_uri` parameter disables the associated `coder_parameter`

dotfiles/main.tf

@@ -16,7 +16,7 @@ variable "agent_id" {
 
 variable "dotfiles_uri" {
   type        = string
-  description = "The URL to a dotfiles repository. (optional)"
+  description = "The URL to a dotfiles repository. (optional, when set, the user isn't prompted for their dotfiles)"
 
   default = null
 }
@@ -59,4 +59,4 @@ resource "coder_script" "dotfiles" {
 output "dotfiles_uri" {
   description = "Dotfiles URI"
   value       = local.dotfiles_uri
-}
+}