As I understand there no percent or auto and it now expects only rate, needs to check
vyos@r14# set qos policy shaper test default bandwidth Possible completions: <number> Bits per second <number>bit Bits per second <number>kbit Kilobits per second <number>mbit Megabits per second <number>gbit Gigabits per second <number>tbit Terabits per second <number>