Missing newline at end of sample_lib.c

**Is your feature request related to a problem? Please describe.**
Clang throws an error about the missing newline at the end of sample_lib.c

**Describe the solution you'd like**
Add a new line, they are pretty cheap these days.

**Describe alternatives you've considered**
None

**Additional context**
None

**Requester Info**
Jacob Hageman - NASA/GSFC