WebKitGTK 2.39.91 released!

This is a development release leading toward 2.40 series.

Rename WebKitWebExtension to WebKitWebProcessExtension in GTK4 API.
Remove WebKitJavascriptResult in favor of using JSCValue directly in GTK4 API.
Add new API to get the request body of WebKitURISchemeRequest.
Make it possible to handle WebKitDownload::decide-destination signal asynchronously.
Allow WebKitDownload destination to be a path instead of a URI.
Make webkit://gpu output exportable as JSON.
Improve scrolling performance in accelerated compositing mode.
Implement KeyboardEvent.repeat.
Fix a crash in MiniBrowser when the favicon is updated.
Fix the build in Ubuntu 20.04 and Debian Stable.
Fix several crashes and rendering issues.
Translation updates: Korean, Polish, Swedish, Korean.

Thanks to all the contributors who made possible this release.