Update prezto

diff --git a/prezto b/prezto
index a104047c8b3ae27ce1e6f836ff4087b1af87d743..4b8ef6562077ddc108d65b3ea2252ee39b1667cc 160000 (submodule)
--- a/prezto
+++ b/prezto
@@ -1 +1 @@
-Subproject commit a104047c8b3ae27ce1e6f836ff4087b1af87d743
+Subproject commit 4b8ef6562077ddc108d65b3ea2252ee39b1667cc