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Updates the requirements on [matplotlib](https://github.com/matplotlib/matplotlib) to permit the latest version.

Updates `matplotlib` to 3.9.0
- [Release notes](https://github.com/matplotlib/matplotlib/releases)
- [Commits](https://github.com/matplotlib/matplotlib/compare/v3.8.4...v3.9.0

)

---
updated-dependencies:
- dependency-name: matplotlib
  dependency-type: direct:development
  dependency-group: major
...
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