Add missing NEWS entry for 7646.
diff --git a/Misc/NEWS b/Misc/NEWS
index 8856d77..86e295e 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -16,6 +16,8 @@
 Library
 -------
 
+- Issue #7646: The fnmatch pattern cache no longer grows without bound.
+
 - Issue #9136: Fix 'dictionary changed size during iteration'
   RuntimeError produced when profiling the decimal module.  This was
   due to a dangerous iteration over 'locals()' in Context.__init__.