Update CHANGELOG.md

Author: sobolevn

CHANGELOG.md

@@ -22,19 +22,7 @@ Semantic versioning in our case means:
 ### Features
 
 - Adds `WPS481`: for statement not allowed in class and module scopes, #3520
-
-
-## 1.6.0
-
-### Features
-
 - Allows `/` string in `WPS226`, #3554
-
-
-## 1.5.0
-
-### Features
-
 - Adds `WPS365`: match statement can be simplified to `if`, #3520
 
 ### Bugfixes