Missing enum member in MergeRequestState "locked"

[Dave-Senn]

Newtonsoft.Json.JsonSerializationException: Error converting value "locked" to type 'GitLabApiClient.Models.MergeRequests.Responses.MergeRequestState'. Path 'state', line 1, position 197.
 ---> System.ArgumentException: Requested value 'locked' was not found.
   at Newtonsoft.Json.Utilities.EnumUtils.ParseEnum(Type enumType, NamingStrategy namingStrategy, String value, Boolean disallowNumber)
   at Newtonsoft.Json.Converters.StringEnumConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer)
   --- End of inner exception stack trace ---
   at Newtonsoft.Json.Converters.StringEnumConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.DeserializeConvertable(JsonConverter converter, JsonReader reader, Type objectType, Object existingValue)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.SetPropertyValue(JsonProperty property, JsonConverter propertyConverter, JsonContainerContract containerContract, JsonProperty containerProperty, JsonReader reader, Object target)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateObject(Object newObject, JsonReader reader, JsonObjectContract contract, JsonProperty member, String id)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)
   at GitLabApiClient.Internal.Http.GitLabApiRequestor.ReadResponse[T](HttpResponseMessage responseMessage)
   at GitLabApiClient.Internal.Http.GitLabApiRequestor.Get[T](String url)
   at GitLabApiClient.MergeRequestsClient.GetAsync(ProjectId projectId, Int32 mergeRequestId)