Error "Resource Conflict: The specified configuration key(s) '[wgserver.authenticate]' cannot be changed." When running "tsm settings import -f <import_file.json>" command

After you configured and applied settings for the identity store of Tableau Server, running the command 
"tsm settings import -f <import_file.json>" to update some settings for the identity store generates the following error:

Resource Conflict: The specified configuration key(s) '[wgserver.authenticate]' cannot be changed.

The import_file.json file looks like this.
 

{
  "configEntities":{
		"identityStore": {
			"_type": "identityStoreType",
			"type": "activedirectory",
...
...
}

Cause