onnxruntime

[WebNN EP] Add quantize Ops (#18011)

### Description
<!-- Describe your changes. -->

Add four quantize Ops: MatmulInteger, ConvInteger, DynamicQuantizeLinear
and DequantizeLinear.
Add datatype TensorProto_DataType_INT8 and TensorProto_DataType_UINT8.

### Motivation and Context
<!-- - Why is this change required? What problem does it solve?
- If it fixes an open issue, please link to the issue here. -->
Support quantized models.