Kusto Cluster: Language Extensions property is not working within PUT operation

Specified language extensions (PYTHON, R) are not considered during a Kusto Cluster PUT operation using the azure-sdk-for-go client.

Used client: https://github.com/Azure/azure-sdk-for-go/blob/master/services/kusto/mgmt/2020-02-15/kusto

PUT specification:
https://github.com/Azure/azure-rest-api-specs/blob/master/specification/azure-kusto/resource-manager/Microsoft.Kusto/stable/2020-02-15/kusto.json#L59

Language extensions are not read-only property, hence they should be usable within a PUT:
https://github.com/Azure/azure-rest-api-specs/blob/master/specification/azure-kusto/resource-manager/Microsoft.Kusto/stable/2020-02-15/kusto.json#L2514

Expected behavior:
Cluster is created and selected language extensions are enabled during PUT operation.

Actual behavior:
Cluster is created, but language extensions won't be activated.

Start by reading the PUT definition near line 59 and the language extensions property near line 2514 in specification/azure-kusto/resource-manager/Microsoft.Kusto/stable/2020-02-15/kusto.json. Compare how the property is represented for PUT with the reported azure-sdk-for-go request. Done means a PUT-created cluster activates the selected PYTHON and R extensions.