[HigherOrderOp] stop erroring out on non-Tensor returns (#107461)
If map or autograd.Function have an input that returns a non-Tensor,
then the code just errors out. Instead of erroring out we should graph
break by raising Unsupported so users aren't confused. The better thing
to do is actually support non-Tensor returns but that requires more
work.
Test Plan:
- new tests
Pull Request resolved: https://github.com/pytorch/pytorch/pull/107461
Approved by: https://github.com/ydwu4
ghstack dependencies: #107459
