webnn: Migrate Reduce validation tests to WPTs
This CL adds WPT tests for reduce and removes the unit tests
MLGraphBuilderTest.ReduceTest, MLGraphTestMojo.ReduceTest and
MLGraphTest.ReduceTest.
Bug: 327337526, 328026885
Change-Id: I26717e0ffdbd2b5cd18f70fb9cefba5d9e719a69
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5496312
Reviewed-by: ningxin hu ningxin.hu@intel.com
Reviewed-by: Austin Sullivan asully@chromium.org
Commit-Queue: Shanxing Mei shanxing.mei@intel.com
Cr-Commit-Position: refs/heads/main@{#1298528}