Update bazlets to latest revision on master

Change-Id: I8d0ecf78b648b30a7f02b2eea42b732ca4d00b5a
diff --git a/WORKSPACE b/WORKSPACE
index 22b3ade..9c27b3c 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "42bffc66c0e92753133e4cea2debe65abc359c4d",
+    commit = "8c91ef43828699c7ed33976897991a427dcfe04b",
     #    local_path = "/home/<user>/projects/bazlets",
 )