Upgrade bazlets to latest stable-2.16 to build with 2.16.12 API

Change-Id: I560e21f0af23cfe88fabe7a906b0e4c13c9ce35e
diff --git a/WORKSPACE b/WORKSPACE
index 62d4892..7df641c 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "6af2e084b72d38a3375925c4586ac2278ef95ee9",
+    commit = "ec989bb514e39447764057c60d3f9959bff8e153",
     #local_path = "/home/<user>/projects/bazlets",
 )