chore: Update gtk-rs crates to 0.17

[ids1024]

Fixes https://github.com/pop-os/keyboard-configurator/issues/180.

Requires a fair number of changes, but behavior should be the same.

[leviport]

• [x] System76 laptop keyboards: galp7, darp5, bonw14
• [x] Launch keyboards: launch_1, launch_heavy_1
• [x] Launch testing mode

Notes:

• Found a bug while testing: https://github.com/pop-os/keyboard-configurator/issues/205. Not a regression.
• Also found https://github.com/pop-os/keyboard-configurator/issues/206 but it is also not a regression

[ids1024]

Amended the commit to fix the example that was failing on CI. But that doesn't change any code that goes into the actually release binaries.