Make main class library project multitargeted .NET5 & .NET6 (Update Nuget references)

Author: Warren Buckley

Our.Umbraco.TagHelpers/Our.Umbraco.TagHelpers.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
 	<PropertyGroup>
-		<TargetFramework>net6.0</TargetFramework>
+		<TargetFrameworks>net5.0;net6.0</TargetFrameworks>
 	</PropertyGroup>
 
 	<PropertyGroup>
@@ -32,15 +32,15 @@
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="Microsoft.AspNetCore.DataProtection.Abstractions" Version="5.0.11" />
+		<PackageReference Include="Microsoft.AspNetCore.DataProtection.Abstractions" Version="6.0.0" />
 		<PackageReference Include="Microsoft.AspNetCore.Mvc.ViewFeatures" Version="2.2.0" />
 		<PackageReference Include="Microsoft.AspNetCore.Razor" Version="2.2.0" />
 		<PackageReference Include="Stubble.Core" Version="1.9.3" />
-		<PackageReference Include="Umbraco.Cms.Core" Version="9.0.1" />
-		<PackageReference Include="Umbraco.Cms.Web.Common" Version="9.0.1" />
+		<PackageReference Include="Umbraco.Cms.Core" Version="9.1.0" />
+		<PackageReference Include="Umbraco.Cms.Web.Common" Version="9.1.0" />
 
-		<PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0" PrivateAssets="All" />
-		<PackageReference Include="GitVersion.MsBuild" Version="5.6.10*" PrivateAssets="All" />
+		<PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="All" />
+		<PackageReference Include="GitVersion.MsBuild" Version="5.8.1" PrivateAssets="All" />
 	</ItemGroup>
 
 	<ItemGroup>