[quant][fix] Add bias once in conv_fused (#48593)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/48593
Previously _conv_forward will add self.bias to the result, so bias is added twice in qat ConvBn module
this PR added a bias argument to _conv_forward and _conv_forward is called with zero bias
in ConvBn module
fixes: https://github.com/pytorch/pytorch/issues/48514
Test Plan: Imported from OSS
Reviewed By: raghuramank100
Differential Revision: D25222215
fbshipit-source-id: 90c0ab79835b6d09622dcfec9de4139881a60746
