Add the ability to toggle disabling touchpad whilst typing

[fossfreedom]

Description

add a switch to control whether to disable the touchpad whilst typing.

Similar to the method added to gnome-control-center here https://gitlab.gnome.org/GNOME/gnome-control-center/-/merge_requests/1998

Submitter Checklist

• [X] Squashed commits with git rebase -i (if needed)
• [X] Built budgie-control-center and verified that the patch worked (if needed)