DotNetDocs 1.2

[robertmclaws]

• Fixed the SDK so it works on machines that do not have Microsoft.Build.NoTargets (inspiration from Streamline docs sdk authoring and end-user experience #13 by @baronfel)
• Implement Documentation Collections through DocumentationReferences
  • Added IDocReferenceHandler to the pipeline so we can "fix up" the generated content
    • Files needed to be moved
    • Links needed to be changed
  • Enhance the Mintlify Provider with IDocReferenceHandler support
  • Update Mintlify.Core with new Mintlify features
  • Change the MintlifyRenderer to use the built-in Badge instead of our custom one
  • Update Icon rendering to use built-in Tailwind styles