No, the “matmul” line is inside the torch_geometric library, and should not be modified.
It says here 13 that the x tensor should be of size [num_nodes, num_node_features], but yours is [1, 11354, 1]. I am guessing you have only 1 node, with 11354 features ?
If so, instead of this “matmul” line, try calling

x = x.squeeze(dim=-1)

to get rid of this last dimension.