Yes drinking raw eggs is good for building muscle.
My brother drank raw eggs when he was working out and building muscles and he did notice an increase in his muscles after he started drinking raw eggs.
Just be sure to drink raw eggs that are pasteurized to avoid getting sick from salmonella or other bacteria.
Raw eggs are a good source of protein and as long as the raw eggs are pasteurized they are healthy to drink or eat raw.
But if they are not pasteurized then the eggs when drank or eaten raw or partially cooked could make you sick.
So do make sure you're drinking pasteurized eggs.
Most eggs bought in stores have been pasteurized so there's not much risk of Salmonella infection.