chore: update CHANGELOG.md for version 1.2.0 release

Author: warioddly

CHANGELOG.md

@@ -1,3 +1,11 @@
+## 1.2.0
+
+* 31 refactor colorutil by @warioddly in https://github.com/warioddly/graphify/pull/33
+* refactor GraphifyController and update dependencies by @warioddly in https://github.com/warioddly/graphify/pull/36
+* refactor: update plugin paths and improve Graphify interface structure by @warioddly in https://github.com/warioddly/graphify/pull/37
+* bump version to 1.2.0 in pubspec.yaml by @warioddly in https://github.com/warioddly/graphify/pull/38
+**Full Changelog**: https://github.com/warioddly/graphify/compare/v1.1.1...v1.2.0
+
 ## 1.1.1
 
 * Fix bug in old versions Flutter "Try changing the name to the name of an existing improvement, or identify an improvement, or a field named "r"."