use metrics-server as example component

Author: tobru

commodore.yml

@@ -1,3 +1,3 @@
 components:
-- name: openshift4-oauth
-  url: https://github.com/appuio/component-openshift4-oauth.git
+- name: metrics-server
+  url: https://github.com/projectsyn/component-metrics-server.git

distribution/k3s.yml

@@ -1 +1,3 @@
 ---
+classes:
+- components.metrics-server