Update CHANGELOG.md

Author: yihuang

CHANGELOG.md

@@ -5,7 +5,7 @@
 ### Bug Fixes
 
 - [#1007](https://github.com/cosmos/iavl/pull/1007) Add the extra check for the reformatted root node in `GetNode`
-- [#]() Fix unlock of unlocked mutex panic.
+- [#1106](https://github.com/cosmos/iavl/pull/1106) Fix unlock of unlocked mutex panic.
 
 ### Improvements