Fixing problem with nuget badge

Author: markolbert

README.md

@@ -2,7 +2,7 @@
 A Net Core 3.1 library for parsing command line arguments 
 in a flexible fashion.
 
-![Nuget](https://img.shields.io/nuget/v/J4JSoftware.CommandLine?style=flat-square)
+[![Nuget](https://img.shields.io/nuget/v/J4JSoftware.CommandLine?style=flat-square)](https://www.nuget.org/packages/J4JSoftware.CommandLine/)
 
 ### TL;DR