mention that lightgbm can use sparse data

Author: EmilHvitfeldt

man/rmd/boost_tree_lightgbm.Rmd

@@ -84,6 +84,11 @@ To effectively enable bagging, the user would also need to set the `bagging_freq
 
 bonsai quiets much of the logging output from [lightgbm::lgb.train()] by default. With default settings, logged warnings and errors will still be passed on to the user. To print out all logs during training, set `quiet = TRUE`.
 
+## Sparse Data
+
+```{r child = "template-uses-sparse-data.Rmd"}
+```
+
 ## Examples 
 
 The "Introduction to bonsai" article contains [examples](https://bonsai.tidymodels.org/articles/bonsai.html) of `boost_tree()` with the `"lightgbm"` engine.