[js/web] Add support for int4/uint4 tensor

[fs-eire]

Description

Add support for int4/uint4 tensor.

[satyajandhyala]

Do we need to add int4 and uint4 data types in js/node/src/tensor_helper.cc also?
I was trying here

onnxruntime/js/node/src/tensor_helper.cc

Line 30 in 219e2b0

static_assert(ONNX_TENSOR_ELEMENT_DATA_TYPE_UINT4 == 21, "definition not consistent with OnnxRuntime");

[fs-eire]

Do we need to add int4 and uint4 data types in js/node/src/tensor_helper.cc also? I was trying here

onnxruntime/js/node/src/tensor_helper.cc

Line 30 in 219e2b0

static_assert(ONNX_TENSOR_ELEMENT_DATA_TYPE_UINT4 == 21, "definition not consistent with OnnxRuntime");

I probably do another change for this. the change may be larger than expected, because it's also using element_size for tensor size calculating, which does not work for (u)int4. (you cannot assign 0.5 to size_t)