Expose the ability for user to cleanup shuffle files

Dynamic scaling on Kubernetes (introduced in Spark 3) depends on only shutting down executors without shuffle files. However Spark does not aggressively clean up shuffle files (see SPARK-5836) and instead depends on JVM GC on the driver to trigger deletes. We already have a mechanism to explicitly clean up shuffle files from the ALS algorithm where we create a lot of quickly orphaned shuffle files. We should expose this as an advanced developer feature to enable people to better clean-up shuffle files improving dynamic scaling of their jobs on Kubernetes.