Update the date of the last release in the changelog.

Author: mondalaci

CHANGELOG.md

@@ -6,7 +6,7 @@ The format is loosely based on [Keep a Changelog](http://keepachangelog.com/en/1
 
 Every Agent version includes the most recent firmware version. See the [firmware changelog](https://github.com/UltimateHackingKeyboard/firmware/blob/master/CHANGELOG.md).
 
-## [1.5.6] - 2020-11-18
+## [1.5.6] - 2020-11-20
 
 Firmware: 8.10.**2** [[release](https://github.com/UltimateHackingKeyboard/firmware/releases/tag/v8.10.2)] | Device Protocol: 4.7.0 | User Config: 4.1.1 | Hardware Config: 1.0.0