Upgrade bazlets to latest stable-2.14 to build with 2.14.19 API

Change-Id: Ic5a4e3e14a6d9b89a5bf7baf77210980eca6cdaf
diff --git a/WORKSPACE b/WORKSPACE
index 67d120c..057aeca 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "10cd2e19ba04fcaaf7edef21b8fc407c699fb9d1",
+    commit = "a920e0c1801a67a2e0803dc149923ff3b81ccc6a",
 )
 
 # Release Plugin API