fix: Add create_tfvars script and update pipeline configuration

gcloud/tf/terraform.tfvars.template

@@ -0,0 +1,13 @@
+// Your GCP project name
+// it will be refererred as the project id
+// in Google Cloud
+// ----------------------------------
+project_name = "${PROJECT_NAME}"
+
+// where to deploy to
+// region
+region = "us-central1"
+zone   = "us-central1-a"
+
+// application name
+app_name = "${PROJECT_NAME}-k3s-cluster"