Fix #57, Remove local error return codes in CF_ValidateConfigTable()

[thnkslprpt]

Checklist

• [x] I reviewed the Contributing Guide.
• [x] I signed and emailed the appropriate Contributor License Agreement to GSFC-SoftwareRelease@mail.nasa.gov and copied cfs-program@lists.nasa.gov.

Describe the contribution

• Fixes #57
  • Removed the local error return codes and replaced with one of the new CFE macros indicating validation failure.

Testing performed GitHub CI actions all passing successfully.

Expected behavior changes CF_ValidateConfigTable() will now return a relevant error code that is intelligible to outside functions, if they want to take action on it. The function is noticeably simpler/cleaner now.

Contributor Info Avi Weiss @thnkslprpt