Update image to v0.24

[antonok-edm]

As I discovered in jaredforth/webp#7 (comment), version v0.23 of the image crate did not support decoding lossless webp images. That caused panics when building a site which called resize_image on any lossless webp image.

As of image v0.24, decoding lossless webp images is now supported.

Sanity check:

• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Code changes

(Delete or ignore this section for documentation changes)

• Are you doing the PR on the next branch?

If the change is a new feature or adding to/changing an existing one:

• Have you created/updated the relevant documentation page(s)?

• N/A, the lack of support for lossless webp images is not already mentioned in the docs anywhere

[Keats]

Thanks for the PR!
Sorry I had a branch that changed all the 3rd party deps that I forgot to merge in next. I've done so now and I've updated image in that.