bca0385862
This PR adds `tvm.testing.CompareBeforeAfter`, a generalization of the `BaseBeforeAfter` utility previously used in `test_tir_transform_simplify.py`, which performs unit tests that perform a transformation on a TIR function and compare the results to an expected TIR output. This arose when minimizing the boilerplate required for unit tests in the implementation of https://github.com/apache/tvm/issues/12261.