Upgrade bazlets to latest stable-2.15

Change-Id: Ia07d3db2ea2bb04338f199cb21e0e8c793fa1aa8

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index 7490955..ee6e636 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "4df6379dfb49746619dcf4764825916406365774",
+    commit = "92f6cad246b41c5b2f9464ecbd4b7c635015319f",
     #local_path = "/home/<user>/projects/bazlets",
 )