Can't find app imputationserver2-pgs for Polygenic Score Calculation

[gjmulder]

The hosted Michigan Imputation Server provides the endpoint:

https://imputationserver.sph.umich.edu/api/v2/jobs/submit/imputationserver2-pgs

It doesn't seem to be provided by https://apps.cloudgene.io/ and I can't find mention of it on Github. Where can I install this app?