chore(docs): update readme(add npm budge)

Author: yicr

README.md

@@ -1,6 +1,7 @@
 # AWS Log Stram Event Trigger
 
 [![GitHub](https://img.shields.io/github/license/gammarers/aws-log-stream-event-trigger?style=flat-square)](https://github.com/gammarers/aws-log-stream-event-trigger/blob/main/LICENSE)
+[![npm (scoped)](https://img.shields.io/npm/v/@gammarers/aws-log-stream-event-trigger?style=flat-square)](https://www.npmjs.com/package/@gammarers/aws-log-stream-event-trigger)
 [![GitHub Workflow Status (branch)](https://img.shields.io/github/actions/workflow/status/gammarers/aws-log-stream-event-trigger/release.yml?branch=main&label=release&style=flat-square)](https://github.com/gammarers/aws-log-stream-event-trigger/actions/workflows/release.yml)
 [![GitHub release (latest SemVer)](https://img.shields.io/github/v/release/gammarers/aws-log-stream-event-trigger?sort=semver&style=flat-square)](https://github.com/gammarers/aws-log-stream-event-trigger/releases)