Split out forward AD tests from test_ops_gradients and reenable slow gradcheck CI (#88216)
Fixes: https://github.com/pytorch/pytorch/issues/88010
This PR does a couple things to stop slow gradcheck from timing out:
- Splits out test_ops_fwd_gradients from test_ops_gradients, and factors out TestFwdGradients and TestBwdGradients which both inherit from TestGradients, now situated in common_utils (maybe there is a better place?)
- Skips CompositeCompliance (and several other test files) for slow gradcheck CI since they do not use gradcheck
- because test times for test_ops_fwd_gradients and test_ops_gradients are either unknown or wrong, we hardcode them for now to prevent them from being put together. We can undo the hack after we see actual test times are updated. ("def calculate_shards" randomly divides tests with unknown test times in a round-robin fashion.)
- Updates references to test_ops_gradients and TestGradients
- Test files that are skipped for slow gradcheck CI are now centrally located in in run_tests.py, this reduces how fine-grained we can be with the skips, so for some skips (one so far) we still use the old skipping mechanism, e.g. for test_mps
Pull Request resolved: https://github.com/pytorch/pytorch/pull/88216
Approved by: https://github.com/albanD
