add agent_id to git_clone

git-clone/README.md

@@ -14,6 +14,7 @@ This module allows you to automatically clone a repository by URL and skip if it
 ```hcl
 module "git-clone" {
     source   = "https://registry.coder.com/modules/git-clone"
+    agent_id = coder_agent.example.id
     url      = "https://github.com/coder/coder"
 }
 ```
@@ -33,6 +34,7 @@ data "coder_git_auth" "github" {
 ```hcl
 module "git-clone" {
     source   = "https://registry.coder.com/modules/git-clone"
+    agent_id = coder_agent.example.id
     url      = "https://github.com/coder/coder"
     path     = "~/projects/coder/coder"
 }