`\vspace` warning with `\lstinputlisting`

[jasigal]

The following minimal example LaTeX file

\documentclass{acmart}
\usepackage{listings}

\begin{document}
\lstinputlisting{test.ml}
\end{document}

where test.ml is

type test = Test

produces the warning

Class acmart Warning: \vspace should only be used to provide space above/below
surrounding objects on input line 5.

twice.

Seems that others have experienced this as well.

I am using a newly downloaded version of TeX Live which includes acmart v2.03.