Bump matplotlib from 3.7.5 to 3.9.4 (#2410)

Bumps [matplotlib](https://github.com/matplotlib/matplotlib) from 3.7.5 to 3.9.4.
- [Release notes](https://github.com/matplotlib/matplotlib/releases)
- [Commits](matplotlib/matplotlib@v3.7.5...v3.9.4)

---
updated-dependencies:
- dependency-name: matplotlib
  dependency-version: 3.9.4
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -34,4 +34,4 @@ sphinx-notfound-page==0.8
 # For fancy twitter previews
 sphinxext-opengraph==0.9.1
 # For social cards
-matplotlib==3.7.5
+matplotlib==3.9.4