Add Version

Author: alexeyzimarev

src/RestSharp/Request/RestRequest.cs

@@ -166,6 +166,11 @@ public RestRequest(Uri resource, Method method = Method.Get)
     /// Can be used to skip container or root elements that do not have corresponding deserialization targets.
     /// </summary>
     public string? RootElement { get; set; }
+    
+    /// <summary>
+    /// HTTP version for the request. Default is Version11.
+    /// </summary>
+    public Version Version { get; set; } = HttpVersion.Version11;
 
     /// <summary>
     /// When supplied, the function will be called before calling the deserializer

src/RestSharp/RestClient.Async.cs

@@ -113,6 +113,7 @@ async Task<HttpResponse> ExecuteRequestAsync(RestRequest request, CancellationTo
         message.Content              = requestContent.BuildContent();
         message.Headers.Host         = Options.BaseHost;
         message.Headers.CacheControl = request.CachePolicy ?? Options.CachePolicy;
+        message.Version              = request.Version;
 
         using var timeoutCts = new CancellationTokenSource(request.Timeout ?? Options.Timeout ?? _defaultTimeout);
         using var cts        = CancellationTokenSource.CreateLinkedTokenSource(timeoutCts.Token, cancellationToken);