enable diagnostics for BindingUnitTests

Author: StephaneDelcroix

docs/design/FeatureSwitches.md

@@ -13,6 +13,8 @@ The following switches are toggled for applications running on Mono for `TrimMod
 | _MauiBindingInterceptorsSupport | Microsoft.Maui.RuntimeFeature.AreBindingInterceptorsSupported | When disabled, MAUI won't intercept any calls to `SetBinding` methods and try to compile them. Enabled by default. |
 | MauiEnableXamlCBindingWithSourceCompilation | Microsoft.Maui.RuntimeFeature.XamlCBindingWithSourceCompilationEnabled | When enabled, MAUI will compile all bindings, including those where the `Source` property is used. |
 | MauiHybridWebViewSupported | Microsoft.Maui.RuntimeFeature.IsHybridWebViewSupported | Enables HybridWebView, which makes use of dynamic System.Text.Json serialization features |
+| EnableDiagnostics | Microsoft.Maui.RuntimeFeature.EnableDiagnostics | Enables diagnostic for the running app |
+| EnableMauiDiagnostics | Microsoft.Maui.RuntimeFeature.EnableMauiDiagnostics | Enables MAUI specific diagnostics, like VisualDiagnostics and BindingDiagnostics. Defaults to EnableDiagnostics |
 
 ## MauiEnableIVisualAssemblyScanning