update librarian

diff --git a/lib/librarian b/lib/librarian
index 7dc1b2c..a0ce0b1 160000 (submodule)
--- a/lib/librarian
+++ b/lib/librarian
@@ -1 +1 @@
-Subproject commit 7dc1b2c84ca9b53454d9eb0c296b4f005dcb780c
+Subproject commit a0ce0b15a412e4bc325470c1801968b8bdd1c7ec