Update README.Rmd

Author: sebffischer

README.Rmd

@@ -96,7 +96,7 @@ tab = as.data.table(mlr_learners)
 tab[sapply(properties, is.element, el = "importance"), key]
 ```
 
-If your learner is not listed here but capable of extracting variable importance from the fitted model, the reason is most likely that it is not yet integrated in the package [mlr3learners](https://github.com/mlr-org/mlr3learners) or the [extra learner organization](https://github.com/mlr-org/mlr3extralearners).
+If your learner is not listed here but capable of extracting variable importance from the fitted model, the reason is most likely that it is not yet integrated in the package [mlr3learners](https://github.com/mlr-org/mlr3learners) or the [extra learner extension](https://github.com/mlr-org/mlr3extralearners).
 Please open an issue so we can add your package.
 
 Some learners need to have their variable importance measure "activated" during learner creation.