Bump imageio-ffmpeg from 0.4.7 to 0.5.1 in /requirements (#1603)

Bumps [imageio-ffmpeg](https://github.com/imageio/imageio-ffmpeg) from 0.4.7 to 0.5.1.
- [Release notes](https://github.com/imageio/imageio-ffmpeg/releases)
- [Commits](imageio/imageio-ffmpeg@v0.4.7...v0.5.1)

---
updated-dependencies:
- dependency-name: imageio-ffmpeg
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Paul Profizi <[email protected]>

Author: dependabot[bot]

requirements/requirements_docs.txt

@@ -2,7 +2,7 @@ ansys_sphinx_theme==0.16.5
 enum-tools[sphinx]==0.12.0
 graphviz==0.20.1
 imageio==2.35.1
-imageio-ffmpeg==0.4.7
+imageio-ffmpeg==0.5.1
 nbsphinx==0.9.3
 pypandoc==1.13
 pytest-sphinx==0.6.3

requirements/requirements_test.txt

@@ -1,7 +1,7 @@
 ansys-platform-instancemanagement==1.1.2
 coverage==7.6.0
 imageio==2.35.1
-imageio-ffmpeg==0.4.7
+imageio-ffmpeg==0.5.1
 pytest==7.4.2
 pytest-cov==5.0.0
 pytest-order==1.2.1