Update imageio to 2.31.4

[pyup-bot]

This PR updates imageio from 2.31.1 to 2.31.4.

Changelog

2.31.4

Fix

* Consistently load GIF frames using the same pixel format ([1036](https://github.com/imageio/imageio/issues/1036)) ([`f4fc7f5`](https://github.com/imageio/imageio/commit/f4fc7f5c49c10cc6da809acc470a70e69ca35248))

2.31.3

Fix

* Refactor resolution metadata reading for TIFF and avoid failing on missing data ([1031](https://github.com/imageio/imageio/issues/1031)) ([`6cd3a42`](https://github.com/imageio/imageio/commit/6cd3a42c7f4371aec61e835d0b3d82fb2e40159f))

Other

* Update readthedocs.yaml ([1035](https://github.com/imageio/imageio/issues/1035)) ([`b0baa1d`](https://github.com/imageio/imageio/commit/b0baa1da25452fd5335261e87e577fdde90f463a))
* Deprecate Python 3.7 support ([1033](https://github.com/imageio/imageio/issues/1033)) ([`61a1e15`](https://github.com/imageio/imageio/commit/61a1e15b3b98cb418b5093c1dafdfc7c0d675d79))

2.31.2

Fix

* Add bytes to ImageResource typehints ([1026](https://github.com/imageio/imageio/issues/1026)) ([`cc35f33`](https://github.com/imageio/imageio/commit/cc35f33d813d340f2532414253171f16fff7a44c))

Other

* Remove deprecations in CD ([1027](https://github.com/imageio/imageio/issues/1027)) ([`d632ea9`](https://github.com/imageio/imageio/commit/d632ea93f306f77fee79fd50f0db0b919168e5c4))
* Fix typo in README.md ([1029](https://github.com/imageio/imageio/issues/1029)) ([`86dcba9`](https://github.com/imageio/imageio/commit/86dcba90d23ba858a6fafb1c26f9f6b6eff19210))
* Fix several typos in the docs and source code comments ([1023](https://github.com/imageio/imageio/issues/1023)) ([`2cdf563`](https://github.com/imageio/imageio/commit/2cdf5632622e00adc8edfadb27dda0b4880e50ba))
* Add migration note for format kwarg ([1019](https://github.com/imageio/imageio/issues/1019)) ([`3dd6574`](https://github.com/imageio/imageio/commit/3dd6574f1a5e52c8a73419d29bbccf6f9e180c23))

Links

• PyPI: https://pypi.org/project/imageio
• Changelog: https://data.safetycli.com/changelogs/imageio/
• Repo: https://github.com/imageio/imageio

[pyup-bot]

Closing this in favor of #6101