chore(deps): bump opencv-python-headless in /backend

Bumps [opencv-python-headless](https://github.com/opencv/opencv-python) from 4.9.0.80 to 4.10.0.84.
- [Release notes](https://github.com/opencv/opencv-python/releases)
- [Commits](https://github.com/opencv/opencv-python/commits)

---
updated-dependencies:
- dependency-name: opencv-python-headless
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

backend/requirements.txt

@@ -51,7 +51,7 @@ pyxlsb==1.0.10
 xlrd==2.0.1
 validators==0.28.1
 
-opencv-python-headless==4.9.0.80
+opencv-python-headless==4.10.0.84
 rapidocr-onnxruntime==1.3.22
 
 fpdf2==2.7.9