fix(coder-labs/modules/sourcegraph-amp): explicitly require external provider (#519)

Co-authored-by: Atif Ali <[email protected]>

Author: uzair-coder07

registry/coder-labs/modules/sourcegraph-amp/README.md

@@ -13,7 +13,7 @@ Run [Amp CLI](https://ampcode.com/) in your workspace to access Sourcegraph's AI
 ```tf
 module "amp-cli" {
   source                  = "registry.coder.com/coder-labs/sourcegraph-amp/coder"
-  version                 = "2.0.0"
+  version                 = "2.0.1"
   agent_id                = coder_agent.example.id
   sourcegraph_amp_api_key = var.sourcegraph_amp_api_key
   install_sourcegraph_amp = true
@@ -48,7 +48,7 @@ variable "amp_api_key" {
 module "amp-cli" {
   count              = data.coder_workspace.me.start_count
   source             = "registry.coder.com/coder-labs/sourcegraph-amp/coder"
-  amp_version        = "2.0.0"
+  amp_version        = "2.0.1"
   agent_id           = coder_agent.example.id
   amp_api_key        = var.amp_api_key # recommended for tasks usage
   workdir            = "/home/coder/project"

registry/coder-labs/modules/sourcegraph-amp/main.tf

@@ -6,7 +6,12 @@ terraform {
       source  = "coder/coder"
       version = ">= 2.7"
     }
+    external = {
+      source  = "hashicorp/external"
+      version = "2.3.5"
+    }
   }
+
 }
 
 variable "agent_id" {