[quant][pt2] Fix no conv bias in convert QAT (#103298)
Summary:
Previously, the QAT pattern for conv + bn with no conv
bias was not actually replaced in convert. This commit adds an
extra pattern in the convert path for this case and the numerics
now match FX's.
Test Plan: python test/test_quantization.py TestQuantizePT2E.test_prepare_qat_conv_bn_fusion_no_conv_bias
Reviewed By: jerryzh168
Differential Revision: D46382819
Pull Request resolved: https://github.com/pytorch/pytorch/pull/103298
Approved by: https://github.com/jerryzh168
