Sizzle: fix a small bug with combinator cache. Fixes #10499.

diff --git a/src/sizzle b/src/sizzle
index 60c254995a01a57c33a36b90ccc4b5a34a98c9d2..a0523a50942971b41af6aba39b39ee81c1fc5f8a 160000 (submodule)
--- a/src/sizzle
+++ b/src/sizzle
@@ -1 +1 @@
-Subproject commit 60c254995a01a57c33a36b90ccc4b5a34a98c9d2
+Subproject commit a0523a50942971b41af6aba39b39ee81c1fc5f8a