Remove Effect type from makeDOMParser?

[bbarker]

This is a bit odd in that if enacted along with #7, would have the effect of completely swapping which functions are currently Effectful - since #7 adds Effect to parse functions, and I suggest removing it here; I couldn't find any explicit reason why new DOMParser should be effectful. The w3c docs do not seem to indicate IO or exceptions as a result of calling the constructor.