quant bench: update observer configs (#42956)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/42956
In preparation for observer perf improvement, cleans up the
micro benchmarks:
* disable CUDA for histogram observers (it's too slow)
* add larger shapes for better representation of real workloads
Test Plan:
```
cd benchmarks/operator_benchmark
python -m pt.qobserver_test
```
Imported from OSS
Reviewed By: supriyar
Differential Revision: D23093996
fbshipit-source-id: 5dc477c9bd5490d79d85ff8537270cd25aca221a
