Update CHANGELOG.md

Author: holtskinner

CHANGELOG.md

@@ -5,6 +5,7 @@
 
 ### Features
 
+* Add support for Python 3.12 ([#203](https://github.com/googleapis/python-documentai-toolbox/issues/203)) ([1ff4bf7](https://github.com/googleapis/python-documentai-toolbox/commit/1ff4bf757a86349402e74d206aca1df677ad9ff1))
 * Introduce compatibility with native namespace packages ([#201](https://github.com/googleapis/python-documentai-toolbox/issues/201)) ([d178acb](https://github.com/googleapis/python-documentai-toolbox/commit/d178acb50a7ad4a0ce0bc7f6fc4550a87dc7a252))
 
 ## [0.11.2-alpha](https://github.com/googleapis/python-documentai-toolbox/compare/v0.11.1-alpha...v0.11.2-alpha) (2023-11-07)