[BE] Remove bool dtype from `masked_scatter` (#98015)
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### <samp>🤖 Generated by Copilot at a9fa438</samp>
Simplified a test function for `torch.masked_scatter` in `test/test_torch.py` by removing redundant and unnecessary code.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/98015
Approved by: https://github.com/ezyang
