Fixed doc references

Author: HeyJoel

src/Cofoundry.Plugins.BackgroundTasks.Hangfire/Cofoundry.Plugins.BackgroundTasks.Hangfire.csproj

@@ -11,7 +11,7 @@
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
-    <DocumentationFile>bin\Release\netcoreapp3.1\Cofoundry.Plugins.BackgroundTasks.Hangfire.xml</DocumentationFile>
+    <DocumentationFile>bin\Release\net6.0\Cofoundry.Plugins.BackgroundTasks.Hangfire.xml</DocumentationFile>
     <NoWarn>1701;1702;1705;1591</NoWarn>
   </PropertyGroup>