Loosen unit test performance assert

[mrwyattii]

We are seeing failures on some runs with the A6000 runner on the DeepSpeed repo. This is due to the multi-replica test having slightly worse performance on that machine that others we have tested. Providing a wider range of accepted performance for now until we figure out why that machine is behaving differently than others.

Example failure:

FAILED test_deployment.py::test_multi_replica[query0-nofail-test-dep-local-50050-False-28080-text-generation-facebook/opt-125m-None-True-2] - AssertionError: two queries should take about the same time as one query
assert 0.8824012279510498 == 0.706052303314209 ± 7.1e-02
  comparison failed
  Obtained: 0.8824012279510498
  Expected: 0.706052303314209 ± 7.1e-02

@loadams