Upgrade bazlets to the latest master revision

Includes "Use now mandatory https protocol for MAVEN_CENTRAL".

Change-Id: I4e83bf9a01f1d2a3bea4ce855709fd33e624fe9a
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
diff --git a/WORKSPACE b/WORKSPACE
index a3463a5..93962da 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -20,7 +20,7 @@
 
 load("//tools:bazlets.bzl", "load_bazlets")
 
-load_bazlets(commit = "09a035e98077dce549d5f6a7472d06c4b8f792d2")
+load_bazlets(commit = "f30a992da9fc855dce819875afb59f9dd6f860cd")
 
 load(
     "@com_googlesource_gerrit_bazlets//tools:maven_jar.bzl",