feat: 从yaml文件注册插件

packages/ui/certd-server/metadata/notification_email.yaml

@@ -0,0 +1,18 @@
+name: email
+title: 电子邮件
+desc: 电子邮件通知
+input:
+  receivers:
+    title: 收件人邮箱
+    component:
+      name: a-select
+      vModel: value
+      mode: tags
+      open: false
+    required: true
+    helper: |-
+      可以填写多个，填写一个按回车键再填写下一个
+      需要先[配置邮件服务器](#/sys/settings/email)
+type: builtIn
+pluginType: notification
+scriptFilePath: ../../../plugins/plugin-notification/index.js