Update docfx.json

Use Windows header in order to meet platform requirements

Author: raprice

docs/docfx.json

@@ -41,7 +41,7 @@
       "feedback_system": "GitHub",
       "feedback_github_repo": "MicrosoftDocs/WindowsCommunityToolkitDocs",
       "feedback_product_url": "https://github.com/windows-toolkit/WindowsCommunityToolkit/issues",
-      "uhfHeaderId": "MSDocsHeader-UWP-Community",
+      "uhfHeaderId": "MSDocsHeader-Windows",
       "ms.topic": "article",
       "ms.prod": "dotnet-communitytoolkit",
       "products": ["https://authoring-docs-microsoft.poolparty.biz/devrel/bcbcbad5-4208-4783-8035-8481272c98b8"],