Adjust `lowpass_filter` cutoff frequency based on timestep (or throw useful exception)

[nickbianco]

trafficstars

Related forum post: https://simtk.org/plugins/phpBB/viewtopicPhpbb.php?f=2402&t=17775&p=50177&start=0&view=

Problematic line: https://github.com/keenon/AddBiomechanics/blob/a37a500ce69a7aa0f6fc2c690653d328e92f94db/server/engine/src/trial.py#L434

[davidpagnon]

Related issue here as well: https://github.com/keenon/AddBiomechanics/issues/262#issuecomment-2137309624