Bump imageio-ffmpeg from 0.4.8 to 0.4.9

Bumps [imageio-ffmpeg](https://github.com/imageio/imageio-ffmpeg) from 0.4.8 to 0.4.9.
- [Release notes](https://github.com/imageio/imageio-ffmpeg/releases)
- [Commits](imageio/imageio-ffmpeg@v0.4.8...v0.4.9)

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

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

Author: dependabot[bot]

pyproject.toml

@@ -77,7 +77,7 @@ doc = [
     "ansys-mapdl-reader==0.52.20",
     "ansys-sphinx-theme==0.11.2",
     "grpcio==1.51.1",
-    "imageio-ffmpeg==0.4.8",
+    "imageio-ffmpeg==0.4.9",
     "imageio==2.31.3",
     "jupyter_sphinx==0.4.0",
     "jupyterlab>=3.2.8",