fix NFSim runtime error on Macos

[jcschaff]

recent build of NFSim on Macos had runtime failures for some models. Rebuild NFSim on Macos paying special attention to memory safety.

[jcschaff]

added fix to branch nonchombo-build and released as v0.0.44-dev3.

see following commits on nonchombo-build branch:

• fix sprintf overflows, missing return values and type warnings in NFSim
• fix build issue with empty dummy.c in sundials (to allow a parent lib)
• upgrade deprecated github actions - artifacts aren't uploaded