Updates the Stan submodule to 396c27a1c.

stan-buildbot · stan-buildbot · commit 182c16d0f5c3 · 2026-02-22T03:42:49.000-05:00
diff --git a/StanHeaders/inst/include/upstream b/StanHeaders/inst/include/upstream
@@ -1 +1 @@
-Subproject commit e905c505da660bfa2b2b80420f22d8dc3bf92e8d
+Subproject commit 396c27a1cae07518afb981e4cd40f22989ec0dc8
