netDx: Version used in F1000Research software paper (BioC 3.12)

Release 1.2.1, as used in the software paper
Pai S et al. (2021). netDx: Software for building interpretable patient classifiers by multi-'omic data integration using patient similarity networks [version 2; peer review: 2 approved]
https://f1000research.com/articles/9-1239

Tested in BioConductor release 3.12.