[R-package] use keyword arguments in internal function calls (#3391)

* [R-package] use keyword arguments in internal function calls

* empty commit

R-package/R/lightgbm.R

@@ -121,7 +121,7 @@ lightgbm <- function(data,
 
   # Check whether data is lgb.Dataset, if not then create lgb.Dataset manually
   if (!lgb.is.Dataset(dtrain)) {
-    dtrain <- lgb.Dataset(data, label = label, weight = weight)
+    dtrain <- lgb.Dataset(data = data, label = label, weight = weight)
   }
 
   train_args <- list(
@@ -152,7 +152,7 @@ lightgbm <- function(data,
   )
 
   # Store model under a specific name
-  bst$save_model(save_name)
+  bst$save_model(filename = save_name)
 
   return(bst)
 }