Can labor & nonlabor transaction be grouped onto the same invoice line

Summary:

Content (please ensure you mask any confidential information):

We are grouping our Project Billing invoices by contract line. We will have certain contract lines with both labor & non-labor transactions, so is it possible to group these onto the same invoice line?

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):