Upgrade bazlets to latest stable-3.0 to build with 3.0.6 API

Change-Id: I8b6f290e4e658833093401ce64bb6924a705cb30

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index 4005492..79bde89 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "7111147b7cf9d9cd4d61f414c815f736f56f0de0",
+    commit = "99d51724c816dc25f03c8ca96126716298a6ee38",
     #local_path = "/home/<user>/projects/bazlets",
 )