[WASM] One MAXIMUM test failed with TF.js WASM backend

[Christywl]

Test Env: webml-polyfill commit: https://github.com/intel/webml-polyfill/commit/a0707ca7a7d26b7fdf52832e27e3d9805b61c9c0

Expected Result: The test should pass.

Actual Result: MAXIMUM test failed with TF.js WASM backend: Error: Broadcasting along outer dims is not yet supported for Maximum.

Note: The test case passed before this commit https://github.com/intel/webml-polyfill/commit/a0707ca7a7d26b7fdf52832e27e3d9805b61c9c0.

How to Reproduce:

1. launch chrome or chromium(disable webml)
2. visit https://brucedai.github.io/webnnt/test/issue_maximum_for_wasm.html?prefer=fast

[akineeic]

It seems that tfjs-wasm doesn't support broadcast in maximum yet, since this case has been excluded in its test. The detailed test content is here.

[ibelem]

@akineeic please file an upstream bug for this issue

[akineeic]

@akineeic please file an upstream bug for this issue

I found that I have mentioned this missing feature in this issue.