SDPB stalls when run with Docker 3.3.0 or 3.3.1 on Intel Mac

[wlandry]

More than one user has reported that sdpb or pvm2sdp will sometimes stall when running under Docker on an Intel Mac. It is not consistent. It can work many times in a row before failing. Restarting Docker.app will let it run again.

One workaround is to use an older version of Docker (3.2.2). This seems to eliminate or at least significantly reduce the frequency of stalls.

Coincidentally, both users discovered this while running sdpb through Mathematica. It is unclear if that is important.