Fix AutoTP test numerical tolerance with rtol (#7794)
Replace torch.allclose() with torch.testing.assert_close() and add rtol
parameter for proper floating-point comparisons in testRowParallel and
testColumnParallel tests.
The tests were failing intermittently in CI because they only used
absolute tolerance (atol) without relative tolerance. Adding rtol allows
for proper numerical comparisons will improve stability of the tests.
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Signed-off-by: Masahiro Tanaka <mtanaka@anyscale.com>
