chore(deps): bump gdk4 from 0.9.6 to 0.10.3

Bumps [gdk4](https://github.com/gtk-rs/gtk4-rs) from 0.9.6 to 0.10.3.
- [Release notes](https://github.com/gtk-rs/gtk4-rs/releases)
- [Changelog](https://github.com/gtk-rs/gtk4-rs/blob/main/CHANGELOG.md)
- [Commits](gtk-rs/gtk4-rs@0.9.6...0.10.3)

---
updated-dependencies:
- dependency-name: gdk4
  dependency-version: 0.10.3
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]