Feat: add an changelog update

CHANGELOG.md

@@ -14,4 +14,21 @@ Sheepy is a lightweight unit testing framework designed for Python developers wh
 
 ### v0.0.2 09/21/2024
 
-changing the entire project structure, reorganizing and changing use cases. Improving to increasingly optimize unit tests.
+changing the entire project structure, reorganizing and changing use cases. Improving to increasingly optimize unit tests.
+
+### v0.0.3 09/22/2024
+
+### Added
+
+* SheepyTestCase: Implementation of the class that automatically registers and runs tests when inheriting.
+* TestOutputFormatter: Module created to format test results, providing a clear and consistent view of the outputs.
+* Assertions Module: Creation of a separate module (asserts.py) that includes assertion methods such as assertEqual, assertTrue, assertFalse, and assertRaises.
+
+### Changed
+
+* Test Execution: Modification of the logic in the SheepyTestCase class to run tests when registering subclasses.
+* Output Formats: Updated the _output_results method to use TestOutputFormatter, improving the presentation of test results.
+* Code Structure: Removed assertion methods from the SheepyTestCase class to centralize the assertion logic in the new module.
+
+### Fixed
+* Error Messages: Improvements in error messages for expected failures and tests.