docs: readme update

Author: adamberecz

README.md

@@ -1,6 +1,6 @@
 <div align="center">
   <a href="https://www.npmjs.com/package/@vueform/multiselect" target="_blank">
-    <img alt="npm" src="https://img.shields.io/npm/dm/@vueform/multiselect?color=%2353ca2f">
+    <img alt="npm" src="https://img.shields.io/npm/dy/@vueform/multiselect?color=%2353ca2f">
   </a>
 
   <img alt="CircleCI" src="https://img.shields.io/circleci/build/github/vueform/multiselect">