Update pybind submodule to v2.13.6

dbort · dbort · commit afe46fd0d392 · 2025-01-08T11:45:14.000-08:00
Our previous pin @8c7b8dd is a random commit after v2.11.1. There
have been 153 commits between that commit and the latest v2.13.6
version.
diff --git a/third-party/pybind11 b/third-party/pybind11
@@ -1 +1 @@
-Subproject commit 8c7b8dd0ae74b36b7d42f77b0dd4096ebb7f4ab1
+Subproject commit a2e59f0e7065404b44dfe92a28aca47ba1378dc4
