docs(changelog): add release notes for 1.8.3

We're doing this final release to update poackage README files for npm.

Author: jelbourn

CHANGELOG.md

@@ -4,6 +4,11 @@ and [read the end of life announcement](https://goo.gle/angularjs-end-of-life).*
 
 **Visit [angular.io](https://angular.io) for the actively supported Angular.**
 
+<a name="1.8.3"></a>
+# 1.8.2 ultimate-farewell (2020-10-21)
+
+One final release of AngularJS in order to update package README files on npm.
+
 <a name="1.8.2"></a>
 # 1.8.2 meteoric-mining (2020-10-21)