Bump opencv-python from 4.5.3.56 to 4.5.4.60 (#448)

Bumps [opencv-python](https://github.com/skvark/opencv-python) from 4.5.3.56 to 4.5.4.60.
- [Release notes](https://github.com/skvark/opencv-python/releases)
- [Commits](https://github.com/skvark/opencv-python/commits

)

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

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

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

requirements.txt

@@ -12,7 +12,7 @@ lxml==4.6.5
 matplotlib==2.2.5
 numpy==1.18.5
 nltk==3.6.5
-opencv-python==4.5.3.56
+opencv-python==4.5.4.60
 pdf2image==1.16.0
 pdfminer.six==20211012
 Pillow>=3.4.1