Update changelog

CHANGES.md

@@ -5,15 +5,27 @@ This document outlines the list of changes to ridgeplot between each release. Fo
 Unreleased changes
 ------------------
 
+### Major changes
+
+- Dropped support for Python 3.7. ([#154](https://github.com/tpvasconcelos/ridgeplot/pull/154))
+
 ### Documentation
 
 - Use the `{raw} html :file: _static/charts/<PLOT-ID>.html` directive to load the interactive Plotly graphs in the generated Sphinx docs. The generated HTML artefacts only include a `<div>` wrapper block now and the plotly.min.js is now vendored and automatically loaded via the `html_js_files` Sphinx config. ([#132](https://github.com/tpvasconcelos/ridgeplot/pull/132))
 - Small adjustments to the example plots in the documentation. ([#132](https://github.com/tpvasconcelos/ridgeplot/pull/132))
 - Reformat markdown files, removing all line breaks. ([#132](https://github.com/tpvasconcelos/ridgeplot/pull/132))
 
+### Internals
+
+- Define a `ridgeplot._missing.MISSING` sentinel object for internal use (this replaces the multiple module-level `_MISSING = object()` sentinels). ([#154](https://github.com/tpvasconcelos/ridgeplot/pull/154))
+- Add an internal `_ridgeplot_examples` package to help with E2E testing and generating plots for the public docs. ([#154](https://github.com/tpvasconcelos/ridgeplot/pull/154))
+
 ### CI/CD
 
 - Replace `isort`, `flake8`, and `pyupgrade` with `ruff`. ([#131](https://github.com/tpvasconcelos/ridgeplot/pull/131))
+- Upgrade CI/CD pipeline to use `cibuildwheel`. ([#154](https://github.com/tpvasconcelos/ridgeplot/pull/154))
+- Simplify and cleanup CI/CD scripts in `./bin`. ([#154](https://github.com/tpvasconcelos/ridgeplot/pull/154))
+- Add regression tests for the figure artifacts generated by the examples in `_ridgeplot_examples`. ([#154](https://github.com/tpvasconcelos/ridgeplot/pull/154))
 
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