Update CHANGELOG.txt

Author: hardbyte

CHANGELOG.txt

@@ -3,8 +3,8 @@ Version 3.3.4
 
 Last call for Python2 support.
 
+* #901 Fix iteration in Bus.stop_all_periodic_tasks
 * #850 Fix socket.error is a deprecated alias of OSError used on Python versions lower than 3.3.
-* #846 Use inter-process mutex to prevent concurrent neoVI device open.
 * #879 Updating incorrect api documentation.
 * #885 Fix recursion message in Message.__getattr__
 * #845 Fix socketcan issue