Feat: add print message example (#5077)

Signed-off-by: FogDong <dongtianxin.tx@alibaba-inc.com>

Signed-off-by: FogDong <dongtianxin.tx@alibaba-inc.com>

references/docgen/def-doc/workflowstep/print-message-in-status.eg.md

@@ -0,0 +1,24 @@
+```yaml
+apiVersion: core.oam.dev/v1beta1
+kind: Application
+metadata:
+  name: print-message-in-status
+  namespace: default
+spec:
+  components:
+  - name: express-server
+    type: webservice
+    properties:
+      image: oamdev/hello-world
+      port: 8000
+  workflow:
+    steps:
+      - name: express-server
+        type: apply-component
+        properties:
+          component: express-server
+      - name: message
+        type: print-message-in-status
+        properties:
+          message: "All addons have been enabled successfully, you can use 'vela addon list' to check them."
+```