Issue #26244: Clarify default zlib compression level in documentation

Based on patch by Aviv Palivoda.
diff --git a/Misc/ACKS b/Misc/ACKS
index 426d19f..b07244a 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1071,6 +1071,7 @@
 Martin Packman
 Shriphani Palakodety
 Julien Palard
+Aviv Palivoda
 Ondrej Palkovsky
 Mike Pall
 Todd R. Palmer