[ONNX] rework some reduction op lowerings (#3870)

- Refactors more "onnx.ReduceXXX" patterns through helper function.
- Fixes bug with iterating unconditionally on `output_dim == 1` during
`dimList` inference.

This change results in passes for the following 11 models:

crossvit_15_240
crossvit_15_dagger_240
crossvit_15_dagger_408
crossvit_18_240
crossvit_18_dagger_240
crossvit_18_dagger_408
crossvit_9_240
crossvit_9_dagger_240
crossvit_base_240
crossvit_small_240
crossvit_tiny_240

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Co-authored-by: Vinayak Dev <[email protected]>

Author: zjgarvey