Upgrade bazlets to latest stable-3.0

download_file.py: Fix root workspace directory detection

Change-Id: I8f90586d8cc5986f8ce7c822aacc90524c021cf5
diff --git a/WORKSPACE b/WORKSPACE
index 078c99b..4c3b85d 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "29ba75f790c68ae2c233a67f7ce1e58e04201ce2",
+    commit = "2118fd30e24f339f5daf5310144dcb7a9123bc90",
     #local_path = "/home/<user>/projects/bazlets",
 )