Bump matplotlib from 3.9.0 to 3.9.1 in /packages/kernel/py/stlite-server

Bumps [matplotlib](https://github.com/matplotlib/matplotlib) from 3.9.0 to 3.9.1.
- [Release notes](https://github.com/matplotlib/matplotlib/releases)
- [Commits](matplotlib/matplotlib@v3.9.0...v3.9.1)

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

Signed-off-by: dependabot[bot] <support@github.com>

packages/kernel/py/stlite-server/pyproject.toml

@@ -14,7 +14,7 @@ requests = "^2.32.3"
 mypy = "^1.11.0"
 streamlit-aggrid = "^1.0.5"
 pandas-stubs = "^2.2.2.240603"
-matplotlib = "^3.9.0"
+matplotlib = "^3.9.1"
 ruff = "^0.5.2"
 pyodide-py = "^0.26.1"