I can think of no Jewish source that considers such an act to be wrong. There are sources that comment that it is natural for a woman's hair to grow longer than a man's (Eruvin 100b), but the sources do not tell us that a women should let her hair grow that long.

If a woman cuts her hair in a manner to make others think she is a man, it would be wrong -- just as it is wrong for a man to cut his body hair so that he looks like a woman (Yoreh De'ah 182:5).

Best wishes,

M. Kornfeld