I'm no Mason but I did watch the National Treasure trilogy a few times! That has got to be similar to staying at a Holiday Inn Express?
Probably Not, anyway.
Unless you are adding the one course to an existing wall or foundation.
IMO there is no need / advantage to mortar as there is nothing to hold them together anyway.
I essentially did the same thing to my Daughters playhouse (roughly the size of your shed) to get the wood up off of the ground, to prevent rot from setting in too early.