fix NPM link

link to https://www.npmjs.com/package/spago/v/next

Author: peterbecich

README.md

@@ -1,6 +1,6 @@
 # spago
 
-![NPM Version (with dist tag)](https://img.shields.io/npm/v/spago/next)
+[![NPM Version (with dist tag)](https://img.shields.io/npm/v/spago/next)](https://www.npmjs.com/package/spago/v/next)
 ![Latest release](https://img.shields.io/badge/dynamic/yaml?url=https%3A%2F%2Fraw.githubusercontent.com%2Fpurescript%2Fspago%2Frefs%2Fheads%2Fmaster%2Fspago.yaml&query=package.publish.version&prefix=v&label=release)
 [![build](https://github.com/purescript/spago/actions/workflows/build.yml/badge.svg)](https://github.com/purescript/spago/actions/workflows/build.yml)
 [![nix-flake](https://github.com/purescript/spago/actions/workflows/nix-flake.yml/badge.svg)](https://github.com/purescript/spago/actions/workflows/nix-flake.yml)