[Darwin] Add NSManagedObjectModel to the leak suppression (#38977)

diff --git a/scripts/tests/chiptest/lsan-mac-suppressions.txt b/scripts/tests/chiptest/lsan-mac-suppressions.txt
index c5f493d..b6c6c26 100644
--- a/scripts/tests/chiptest/lsan-mac-suppressions.txt
+++ b/scripts/tests/chiptest/lsan-mac-suppressions.txt
@@ -71,5 +71,6 @@
 # TLS storage
 leak:CRYPTO_set_thread_local
 
-# Not our leak, clearly:
+# Not our leaks, clearly:
 leak:CFXNotificationRegistrarFind
+leak:NSManagedObjectModel