Source: Starfinder Core Rulebook p.77
Your drone is outfitted with cargo space. The drone's Strength score counts as 4 higher for the purpose of how determining much bulk it can carry, but all of this extra bulk must be stored gear and cargo, not mounted weapons, armor mods, or the like. This does not affect the drone's actual Strength score in any way, merely how much it can carry. Due to its size, a drone might still be unable to carry awkward or unwieldy items.