Not wishing to be an 'internet general' but:
This is pointless. The purpose of a machine gun of this calibre is suppressing fire - keep the enemy's heads down while you charge their position.
A remote drone that does this is pointless
A wheeled remote drone is even more pointless.
Small and wheeled has the advantage over a flying drone that it can carry more payload, and is faster than a tracked vehicle - but is limited to roads.
So a 'remote control car' mine that can drive into a convoy and give a vehicle a "significant emotional event" = useful. especilly if autonomous so you can set it goign and run away.
But a drone that is supposed to drive over urban rubble or fields, but with 2inch high wheels, and then stop and sweep the enemy with machine gun fire for 30secs (until it runs out of ammo or needs a barrel change) from a height of 12inches ?