fix unsqueeze2+conv2d quantization (#49164)

python/paddle/static/quantization/post_training_quantization.py

@@ -659,8 +659,12 @@ class PostTrainingQuantization:
                     _logger.warning(
                         op_type + " is not supported for quantization."
                     )
+                is_conv1d_quant = (op_type == "unsqueeze2") and (
+                    utils._get_op_input_var_names(op)[0]
+                    in persistable_var_names
+                )
                 # For quantized ops, sample inputs and outputs
-                if op_type in self._quantizable_op_type:
+                if op_type in self._quantizable_op_type or is_conv1d_quant:
                     collect_var_name(
                         utils._get_op_input_var_names(op),
                         persistable_var_names,