Any variety of dwarf works fine for the Artificer, though the Mountain Dwarf’s armor proficiencies are wasted. Hill Dwarf is a great choice for front-line artificers because the additional hit points bring you more in line with martial classes like the Fighter, but Mark of Warding’s access to Armor of Agathys can solve the same problem.

Hill: Hill dwarfs get a Wisdom increase, which makes them ideal clerics and druids, but not much else. You could also try hill dwarf monks and rangers, but without a Dexterity increase you’ll fall behind other characters offensively. Mountain: Mountain dwarfs get a Strength increase, which makes them good barbarians, fighters, and paladins.