Functionally it doesn’t matter. The elements (LED and load resistor) are in series so the current flowing through them will be the same regardless of the order in which they're hooked up.

That said, if the LED is driven on the low side I have a preference to put the load resistor from VDD to LED anode. Reason? Connected this way, if there’s a short to GND at the anode (from, say, an errant scope probe) then it won’t kill the LED. Conversely, if the LED anode is tied to VDD and the load resistor to the cathode, shorting the LED cathode puts the full supply across the LED, which makes a nice popping noise...