buildx/driver/kubernetes/podchooser
Justin Chadwell d9ef9bec34 kubernetes: add error when no pods available
This prevents the fall-through to the panic from division by zero in the
modulus below, and presents a neater error to the user.

Signed-off-by: Justin Chadwell <me@jedevc.com>
..
podchooser.go kubernetes: add error when no pods available