dependency: (deps): bump matplotlib from 3.9.3 to 3.9.4 in /backend (#…

…451)

Bumps [matplotlib](https://github.com/matplotlib/matplotlib) from 3.9.3 to 3.9.4.
- [Release notes](https://github.com/matplotlib/matplotlib/releases)
- [Commits](matplotlib/matplotlib@v3.9.3...v3.9.4)

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

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

backend/requirements.txt

@@ -27,7 +27,7 @@ httpx==0.28.1
 idna==3.10
 inflection==0.5.1
 kiwisolver==1.4.7
-matplotlib==3.9.3
+matplotlib==3.9.4
 numpy==1.26.4
 openai==1.57.3
 opencv-python==4.10.0.84