Bump opencv-python from 4.6.0.66 to 4.8.1.78 in /tests/e2e_tests

Bumps [opencv-python](https://github.com/opencv/opencv-python) from 4.6.0.66 to 4.8.1.78.
- [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]>

tests/e2e_tests/requirements.txt

@@ -7,7 +7,7 @@
 py-cpuinfo==7.0.0
 scipy>=1.5.4,<1.12
 opencv-python>=4.5; sys_platform != "darwin"
-opencv-python==4.6.0.66; sys_platform == "darwin"
+opencv-python==4.8.1.78; sys_platform == "darwin"
 unittest-xml-reporting==3.0.4
 lpips==0.1.3