Shift to Unity testing framework

Feature Description

This merge request transitions MicroCART from using a lightweight testing framework made by last year's team to the Unity testing suite, addressing (part of) Issue #20 (closed)

Implementation Details

• Unity was added to the top level of the repo
• Each of the three existing tests that referenced the existing testing framework were updated to use Unity
  • test_queue.c
  • test_quad_app.c
  • test_computation_graph.c
• Makefiles were modified to use Unity and define UNITY_INCLUDE_CONFIG_H so the Unity config header is referenced

Impacted Areas

• Quad Software
• Testing