[js/webgpu] Fix issue to run model demucs (#22074)
This is to fix issue #22031 to run model demucs.
For conv-transpose, outputPadding.length could be 1, while spatialRank
is 2. The fix is to append enough 0s to outputPadding. For conv, the
issue is similar. kernelShape.length sometimes could be 1, while
inputs[1].dims.length is 4. The fix is also to append enough 0s to
kernelShape.
