Update gtk4 crate
Newly built versions of fragments crashes at startup with message:
thread 'main' panicked at 'Failed to retrieve template child. Please check that it has been bound and has a #[template_child] attribute.', /build/fragments/cargo-home/registry/src/github.com-1ecc6299db9ec823/gtk4-0.4.8/src/subclass/widget.rs:1305:17
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Executing cargo update -p gtk4
before build fixes the issue