Bump matplotlib from 3.8.3 to 3.8.4 (#4130)

Bumps [matplotlib](https://github.com/matplotlib/matplotlib) from 3.8.3 to 3.8.4.
- [Release notes](https://github.com/matplotlib/matplotlib/releases)
- [Commits](https://github.com/matplotlib/matplotlib/compare/v3.8.3...v3.8.4)

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

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

requirements.txt

@@ -5,7 +5,7 @@ imbalanced-learn==0.12.2
 libmozdata==0.2.4
 lmdb==1.4.1
 markdown2==2.4.13
-matplotlib==3.8.3
+matplotlib==3.8.4
 mercurial==6.5.3
 microannotate==0.0.24
 mozci==2.4.0