Upgrade to latest MTG (Azure#50561)

Author: JoshLove-msft

eng/Packages.Data.props

@@ -442,7 +442,7 @@
 
   <PropertyGroup>
     <TestProxyVersion>1.0.0-dev.20250501.1</TestProxyVersion>
-    <UnbrandedGeneratorVersion>1.0.0-alpha.20250611.1</UnbrandedGeneratorVersion>
+    <UnbrandedGeneratorVersion>1.0.0-alpha.20250611.5</UnbrandedGeneratorVersion>
     <AzureGeneratorVersion>1.0.0-alpha.20250527.2</AzureGeneratorVersion>
   </PropertyGroup>
 </Project>

eng/packages/http-client-csharp/package-lock.json

@@ -38,7 +38,7 @@
     "dist/generator/**"
   ],
   "dependencies": {
-    "@typespec/http-client-csharp": "1.0.0-alpha.20250611.1"
+    "@typespec/http-client-csharp": "1.0.0-alpha.20250611.5"
   },
   "devDependencies": {
     "@azure-tools/azure-http-specs": "0.1.0-alpha.17",