fix yaml format (#2)

currently the generated yaml file cant be read

Author: etwillbefine

config.tpl

@@ -1,9 +1,9 @@
 clusterID: ${cluster_id}
-  server:
-    mapRoles:
-    - roleARN: ${admin_iam_role_arn}
-      username: ${admin_k8s_username}
-      groups: ${admin_k8s_groups}
-    - roleARN: ${readonly_iam_role_arn}
-      username: ${readonly_k8s_username}
-      groups: ${readonly_k8s_groups}
+server:
+  mapRoles:
+  - roleARN: ${admin_iam_role_arn}
+    username: ${admin_k8s_username}
+    groups: ${admin_k8s_groups}
+  - roleARN: ${readonly_iam_role_arn}
+    username: ${readonly_k8s_username}
+    groups: ${readonly_k8s_groups}