[quant] Fix flaky test test_histogram_observer_against_reference (#46957)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/46957
Possibly due to use of large tensor in hypothesis. Reducing the size to see if it helps
Test Plan:
python test/test_quantization.py TestRecordHistogramObserver.test_histogram_observer_against_reference
Imported from OSS
Reviewed By: jerryzh168
Differential Revision: D24580137
fbshipit-source-id: f44ab059796fba97cccb12353c13803bf49214a1
