Upgrade bazlets to latest stable-2.16

Includes further fixes for --incompatible_disallow_legacy_java_provider.

Change-Id: I4ef0a1b7ef2a28e2e8b134207b69d69dc46b3666
diff --git a/WORKSPACE b/WORKSPACE
index f6fdf51..d20b2bf 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "3df1fac2202ac2a42cec61fac8c502178c9af391",
+    commit = "6af2e084b72d38a3375925c4586ac2278ef95ee9",
     #local_path = "/home/<user>/projects/bazlets",
 )