rotate-and-reduce: support variations on simple reduction patterns

[j2kun]

For example:

• when one of the operations in the reduction is not a tensor element, but the operation is commutative so it can be moved to the end.

[github-actions[bot]]

This issue has 2 outstanding TODOs:

• lib/Dialect/TensorExt/Transforms/RotateAndReduce.cpp:103: support these non-tensor-extract operands by
• tests/tensor_ext/rotate_and_reduce.mlir:278: support this

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