Upgrade bazlets to latest stable-2.15

Change-Id: Iba6f974fe614277eac691dcd76cc59d3990454fe
diff --git a/WORKSPACE b/WORKSPACE
index 579ea2b..a4666cc 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"
 )