Upgrade bazlets to latest stable-3.0 to build with 3.0.9 API

Change-Id: If52816b7e8b23abb540f27a55b9c5a2a06309a08
diff --git a/WORKSPACE b/WORKSPACE
index 78d50d0..58901b3 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "97eef86854b0fb68b9287831f3075b6f6218ff41",
+    commit = "15eae2ee5cd524a204bd62c3d59bfd0ce86916ec",
     #local_path = "/home/<user>/projects/bazlets",
 )