Sample app test doesn't end up in exe dir after make install

[skliper]

Describe the bug
sample_app-sample_app-testrunner doesn't get "installed"

To Reproduce
Steps to reproduce the behavior:

1. make SIMULATION=native ENABLE_UNIT_TEST=true prep; make; make install
2. ls build/exe/cpu1
3. find /. -name "sample_app_sample_app-testrunner"

Expected behavior
Install should move all tests to install directory

Code snips
N/A

System observed on:

• Hardware: cFS Dev 3
• OS: Ubuntu 18.04
• Versions: observed in refactored IC at skliper/ic-20200511-jh

Additional context
N/A

Reporter Info
Jacob Hageman - NASA/GSFC