Merge pull request #157 from terraform-google-modules/example-tests

Make examples in READMEs runnable and testable

modules/gke-nodepool/README.md

@@ -24,13 +24,14 @@ To have the module auto-create a service account for the nodes, set the `node_se
 
 ```hcl
 module "cluster-1-nodepool-1" {
-  source                      = "../modules/gke-nodepool"
+  source                      = "./modules/gke-nodepool"
   project_id                  = "myproject"
   cluster_name                = "cluster-1"
   location                    = "europe-west1-b"
   name                        = "nodepool-1"
   node_service_account_create = true
 }
+# tftest:modules=1:resources=1
 ```
 
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