Enable WEBP support for the logo

I have created a MR that adds support for webp images.

checking

Code review pass, all are looking ok.

Testing without the fix against current 4.0.x I couldn't upload a WebP logo.
Applying the fix I could upload a WebP logo and I could see it in the sidebar.

Approved.
Well done

Here is the change record 'file_validate and related functions are deprecated and replaced with file.validator service and Constraint plugins': https://www.drupal.org/node/3363700 →