Add fsw/src to app target

[chillfig]

Checklist (Please check before submitting)

• I reviewed the Contributing Guide.
• I performed a cursory search to see if the bug report is relevant, not redundant, nor in conflict with other tickets.

Describe the bug
Cannot build cert_testbed. target_include_directories(xx PUBLIC fsw/src) is needed to build tables, etc. Revise CMakeLists.txt

To Reproduce
Build in cert_testbed

Expected behavior
Error-free build

Code snips
If applicable, add references to the software.

System observed on:

• Ubuntu 20.04

Additional context
N/A

Reporter Info
Justin Figueroa, Vantage Systems

[chillfig]

cert_testbed required changes elsewhere to resolve build errors. The option to include fsw/src to app target from the open-source code is not preferred.