docs(CHANGES) Visual API docs improvements via gp-sphinx

why: Capture the api-styling migration to the gp-sphinx package
stack in the unreleased notes.
what:
- Add a Documentation bullet under g 0.0.10
  linking to the project PR

Author: tony

CHANGES

@@ -33,6 +33,11 @@ $ uvx --from 'g' --prerelease allow g
 _Notes on upcoming releases will be added here_
 <!-- END PLACEHOLDER - ADD NEW CHANGELOG ENTRIES BELOW THIS LINE -->
 
+### Documentation
+
+- Visual improvements to API docs from [gp-sphinx](https://gp-sphinx.git-pull.com)-based Sphinx packages (#53)
+
+
 ### CLI
 
 - `g --version` and `g -V` now display g's version instead of being passed to