#11496: skip history test if clear_history is not available.

Patch by Natalia B. Bidart.
diff --git a/Misc/ACKS b/Misc/ACKS
index a11bcf0..a1197ad 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -79,6 +79,7 @@
 Steven Bethard
 Stephen Bevan
 Ron Bickers
+Natalia B. Bidart
 Adrian von Bidder
 David Binger
 Dominic Binks