temp(ci): try macOS 26 for .NET MAUI

Author: Teodor Ciuraru

.github/workflows/dotnet-maui-ci.yml

@@ -93,7 +93,7 @@ jobs:
 
   build-ios:
     name: Build iOS
-    runs-on: macos-latest
+    runs-on: macos-26
     needs: lint
     timeout-minutes: 60