Bump opencv-contrib-python-headless from 4.5.5.62 to 4.8.1.78 in /src

Bumps [opencv-contrib-python-headless](https://github.com/opencv/opencv-python) from 4.5.5.62 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-contrib-python-headless
  dependency-type: direct:production
...

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

src/requirements.txt

@@ -21,4 +21,4 @@ psycopg2-binary==2.9.3
 apprise==0.9.3
 cryptography<3.4  # before rust requirement
 numpy==1.22.2
-opencv-contrib-python-headless==4.5.5.62
+opencv-contrib-python-headless==4.8.1.78