feat: Move unoapp-winui-net6 to unoapp

Author: jeromelaban

src/SolutionTemplate/Uno.ProjectTemplates.Dotnet/content/unoapp-winui-net6/.template.config/dotnetcli.host.json renamed to src/SolutionTemplate/Uno.ProjectTemplates.Dotnet/content/unoapp/.template.config/dotnetcli.host.json

@@ -22,7 +22,7 @@
     "language": "C#",
     "type": "project"
   },
-  "shortName": "unoapp-winui-net6",
+  "shortName": "unoapp",
   "sourceName": "UnoWinUIQuickStart",
   "defaultName": "UnoApp",
   "placeholderFilename": "template-ignore",

src/SolutionTemplate/Uno.ProjectTemplates.Dotnet/content/unoapp-winui-net6/.template.config/template.json renamed to src/SolutionTemplate/Uno.ProjectTemplates.Dotnet/content/unoapp/.template.config/template.json

@@ -1,4 +1,4 @@
-{
-    // required until .NET 6.0.300 is published
-    "sdk": { "allowPrerelease": true }
+{
+    // required until .NET 6.0.300 is published
+    "sdk": { "allowPrerelease": true }
 }