chore(deps): update opencv-python requirement

Updates the requirements on [opencv-python](https://github.com/opencv/opencv-python) to permit the latest version.
- [Release notes](https://github.com/opencv/opencv-python/releases)
- [Commits](https://github.com/opencv/opencv-python/commits)

---
updated-dependencies:
- dependency-name: opencv-python
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -3,4 +3,4 @@ tensorflow
 numpy
 calango
 mediapipe
-opencv-python~=4.7.0.72
+opencv-python~=4.8.1.78