Bump imageio from 2.19.3 to 2.19.5 (#312)

Bumps [imageio](https://github.com/imageio/imageio) from 2.19.3 to 2.19.5.
- [Release notes](https://github.com/imageio/imageio/releases)
- [Changelog](https://github.com/imageio/imageio/blob/master/CHANGELOG.md)
- [Commits](imageio/imageio@v2.19.3...v2.19.5)

---
updated-dependencies:
- dependency-name: imageio
  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/requirements_docs.txt

@@ -2,7 +2,7 @@ pypandoc==1.8.1
 matplotlib==3.5.2
 vtk<9.1.0
 pyvista==0.35.1
-imageio==2.19.3
+imageio==2.19.5
 imageio-ffmpeg==0.4.7
 Sphinx==5.0.2
 nbsphinx==0.8.9