Keyboard group keyboards should not call sway_keyboard_configure. They
do not have an input config and they derive their state from the
keyboards within the group.
For some reason, I got sway_keyboard_configure and
seat_configure_keyboard mixed up and thought seat_reset_device called
the latter.
Calling sway_keyboard_configure with a keyboard group's keyboard is not
supported and can cause issues. If any clients are listening to the ipc
input event, a sigsegv will occur due to not every property - such as
identifier - being wired up for keyboard group keyboard's.
This also adds an assertion to sway_keyboard_configure to ensure that
this does not occur in the future and any instances are quickly caught.
5c32a48453