feat(Accordion): add multiple prop and close others by default (#364)

Co-authored-by: Benjamin Canac <canacb1@gmail.com>

src/runtime/utils/StateEmitter.ts

@@ -0,0 +1,22 @@
+import { watch, defineComponent } from 'vue'
+
+export default defineComponent({
+  props: {
+    open: {
+      type: Boolean,
+      default: false
+    }
+  },
+  emits: ['open', 'close'],
+  setup (props, { emit }) {
+    watch(() => props.open, (value) => {
+      if (value) {
+        emit('open')
+      } else {
+        emit('close')
+      }
+    })
+
+    return () => {}
+  }
+})