KinematicCharacterController: early break in move_shape in case of no update.

[PieroV]

Hi! I think the while in move_shape could be early-broken if no improvement is done in an iteration: if I understand correctly, if the character has not moved in an iteration, it will not in the next one, too.
However, all the collision queries will be run, consuming time.
But I am not sure this makes sense, since kinematic_friction_translation is also updated during iterations.

[PieroV]

@sebcrozet hi, you asked me to send a simple example of the problem that patch should solve on Discord, so here it is 🙂 : simpletest.zip.

Please notice also that I would expect grounded to become true eventually, but it does not (both with and without my patch). Maybe I can open an issue for that, unless I found a way to solve the problem.