docs(CHANGELOG.md): update

Author: sciborrudnicki

CHANGELOG.md

@@ -6,6 +6,37 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [1.0.3] - 2021-08-06
+
+### 1.0.3 Added
+
+- [`5752d9e`][5752d9e]  
+  Tests for the `MessageFunctionBuilder`.
+- [`488270d`][5752d9e]  
+  Tests for the `MessageBuilder`.
+
+[5752d9e]: https://github.com/angular-package/error/commit/5752d9e7b3631dcca0d6945e25a92d1fdfb9eee3
+[488270d]: https://github.com/angular-package/error/commit/488270d4c88f8575c8289022559e4f8ce1de828b
+
+### 1.0.3 Changed
+
+- [`5bd6a2b`][5bd6a2b]  
+  jsdoc description of the `MessageBuilder`.
+- [`1dffd31`][1dffd31]
+  Updated `README.md`.
+
+[5bd6a2b]: https://github.com/angular-package/error/commit/5bd6a2bf8dc98db6666f8d84bb28771357f17105
+[1dffd31]: https://github.com/angular-package/error/commit/1dffd31ab4db736a4f583ac4d3c1994c92da92ea
+
+### 1.0.3 Fixed
+
+- [`5427c65`][5427c65]  
+  Added message builder to api.
+
+[5427c65]: https://github.com/angular-package/error/commit/5427c6585ddebe01bc6e3733425e07b924ec0ca6
+
+----
+
 ## [1.0.2] - 2021-08-04
 
 ### 1.0.2 Update