Add justifications for suppressing the warnings from JsonSerializer.

src/Http/Http.Extensions/gen/RequestDelegateGeneratorSources.cs

@@ -150,7 +150,7 @@ private static Func<HttpContext, StringValues> ResolveFromRouteOrQuery(string pa
 
     public static string WriteToResponseAsyncMethod => """
         [UnconditionalSuppressMessage("Trimming", "IL2026:RequiresUnreferencedCode",
-            Justification = "<Pending>")]
+            Justification = "The 'JsonSerializer.IsReflectionEnabledByDefault' feature switch, which is set to false by default for trimmed ASP.NET apps, ensures the JsonSerializer doesn't use Reflection.")]
         [UnconditionalSuppressMessage("AOT", "IL3050:RequiresDynamicCode", Justification = "See above.")]
         private static Task WriteToResponseAsync<T>(T? value, HttpContext httpContext, JsonTypeInfo<T> jsonTypeInfo, JsonSerializerOptions options)
         {

src/Http/Http.Results/src/HttpResultsHelper.cs

@@ -21,7 +21,7 @@ internal static partial class HttpResultsHelper
     private static readonly Encoding DefaultEncoding = Encoding.UTF8;
 
     [UnconditionalSuppressMessage("Trimming", "IL2026:RequiresUnreferencedCode",
-        Justification = "<Pending>")]
+        Justification = "The 'JsonSerializer.IsReflectionEnabledByDefault' feature switch, which is set to false by default for trimmed ASP.NET apps, ensures the JsonSerializer doesn't use Reflection.")]
     [UnconditionalSuppressMessage("AOT", "IL3050:RequiresDynamicCode", Justification = "See above.")]
     public static Task WriteResultAsJsonAsync<TValue>(
         HttpContext httpContext,

src/Shared/RouteHandlers/ExecuteHandlerHelper.cs

@@ -35,7 +35,7 @@ public static void SetPlaintextContentType(HttpContext httpContext)
     }
 
     [UnconditionalSuppressMessage("Trimming", "IL2026:RequiresUnreferencedCode",
-        Justification = "<Pending>")]
+        Justification = "The 'JsonSerializer.IsReflectionEnabledByDefault' feature switch, which is set to false by default for trimmed ASP.NET apps, ensures the JsonSerializer doesn't use Reflection.")]
     [UnconditionalSuppressMessage("AOT", "IL3050:RequiresDynamicCode", Justification = "See above.")]
     public static Task WriteJsonResponseAsync<T>(HttpResponse response, T? value, JsonSerializerOptions options, JsonTypeInfo<T> jsonTypeInfo)
     {