docs(changelog): add project directory structure entry

Added an entry that the implicit Python project directory
structure assumptions have been removed to the changelog.

docs/CHANGELOG.md

@@ -12,6 +12,7 @@
 
 - Replaced the installation instructions, which used the old registry, with a reference to the Gitea Package Registry in README
 - Made Python function signatures (argument default values) compliant with PEP 8
+- Removed implicit Python project directory structure assumptions
 
 ### Deprecated