Added license link to the nuget package

Author: anttikajanus

src/tanka-graphql-net-client/Tanka.GraphQL.Net.Client.csproj

@@ -20,6 +20,7 @@
     <Version>0.0.0</Version>
     <AssemblyVersion>0.0.0.0</AssemblyVersion>
     <FileVersion>0.0.0.0</FileVersion>
+    <PackageLicenseUrl>https://github.com/anttikajanus/tanka-graphql-net-client/blob/master/LICENSE</PackageLicenseUrl>
 </PropertyGroup>
 
   <ItemGroup>