If something is ‘as good luck would have it’ it has come about by some fortunate chance.

This expression is first found in Shakespeare’s The Merry Wives of Windsor, 1600:

FALSTAFF:

You shall hear. As good luck would have it, comes in one Mistress Page; gives intelligence of Ford’s approach; and, in her invention and Ford’s wife’s distraction, they conveyed me into a buck-basket.