Merge with dev

Author: alexeyzimarev

src/Directory.Build.props

@@ -15,6 +15,7 @@
         <SymbolPackageFormat>snupkg</SymbolPackageFormat>
         <GenerateDocumentationFile>true</GenerateDocumentationFile>
         <NoWarn>$(NoWarn);1591</NoWarn>
+        <LangVersion>11</LangVersion>
     </PropertyGroup>
 
     <ItemGroup>

src/RestSharp/Extensions/HttpResponseExtensions.cs

@@ -19,7 +19,7 @@ public static class HttpResponseExtensions {
     internal static Exception? MaybeException(this HttpResponseMessage httpResponse)
         => httpResponse.IsSuccessStatusCode
             ? null
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
             : new HttpRequestException($"Request failed with status code {httpResponse.StatusCode}");
 #else
             : new HttpRequestException($"Request failed with status code {httpResponse.StatusCode}", null, httpResponse.StatusCode);