If that's not the case, or you're considering not taking it next semester or whatever, I would still encourage you to stick with it, for a few reasons.
First, to be frank it sounds as though you aren't nearly as good at music theory as you think you are. 20 intervals should take at most 5 minutes to identify, even if they're all crazy ones like triply augmented 10ths or whatever. If it's taking you significantly more than that then you clearly are nowhere near proficient in them. Transposition is also important to know, even if it's not on your final, and also shouldn't take much time to do. I assume those assignments sound "stupid" to you because you see them as unnecessary, but if you truly had little or nothing left to learn from them, then they would take you so little time that they would not be a "burden" at all. You may think you've learned most of the curriculum for the full year, but based on your stated examples, I think you would learn a lot by leaving your ego at the door and taking the class more seriously.
Second, you might be able to get out of a semester or two of college theory, either directly if it's AP theory or by testing out, if you have a firm grasp of the basics (probably up through basic four part harmonies). That would be well worth it.
Lastly, your teacher hating you is unfortunately not a compelling reason. The occasional lousy teacher/professor is inevitable, and while it sucks, it's usually not worth dropping a course over. I've found that when teachers dislike me, if I make a concerted effort to always be polite, humble, and completely on top of homework and tests in their class, they notice fairly quickly and become much less unpleasant. I would try that and see if she doesn't become much easier to deal with.
Best of luck.