Update Sizzle to fix oldIE erroneous getAttribute invokification.

diff --git a/src/sizzle b/src/sizzle
index b54d43719eb35e229816dd09da9c12a52a772d54..6d6f55a07d234fd33ad0a96a94fa4a640b8058b0 160000 (submodule)
--- a/src/sizzle
+++ b/src/sizzle
@@ -1 +1 @@
-Subproject commit b54d43719eb35e229816dd09da9c12a52a772d54
+Subproject commit 6d6f55a07d234fd33ad0a96a94fa4a640b8058b0