fix(imperative/quantization): add conditional when passing parameters name

GitOrigin-RevId: f38042aeabd653cbc23a744de581b550135c0a86

imperative/python/megengine/module/quantized/conv_bn.py

@@ -40,7 +40,9 @@ class _ConvBnActivation2d(Conv2d):
         )
         weight = w_fold.astype(qat_module.get_weight_dtype())
         qconv.weight = Parameter(weight.numpy(), name=qat_module.conv.weight.name)
-        qconv.bias = Parameter(b_fold.numpy(), name=qat_module.conv.bias.name)
+        qconv.bias = Parameter(b_fold.numpy())
+        if qat_module.conv.bias is not None:
+            qconv.bias.name = qat_module.conv.bias.name
         return qconv