Add Version to RestRequest

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);