RUSTSEC-2024-0412: gtk-rs GTK3 bindings - no longer maintained

[github-actions]

gtk-rs GTK3 bindings - no longer maintained

Details
Status	unmaintained
Package	gdk
Version	0.18.2
URL	gtk-rs/gtk3-rs@508a69b
Date	2024-03-04

The gtk-rs GTK3 bindings are no longer maintained.

The maintainers have archived the repository, and added a note to the crate
description and its README.md that the crates are no longer maintained.

Please take a look at gtk4-rs instead.

See [advisory page](https://rustsec.org/advisories/RUSTSEC-2024-0412.html) for additional details.