Add Unit tests for GraphMatrix.hpp

[SharonIV0x86]

A testing suite has been added to Appledore. Please review the pull request #59 to get familiar with how the tests are structured and how you can add additional tests.

Below are the functions in GraphMatrix.hpp that need to be tested:

Tasks

• Add tests for getEdge function.
• Add tests for findAllPaths.
• Add tests for isConnected.
• Add tests for removeVertex.
• Add tests for getIsolated.

[tulu-g559]

@SharonIV0x86
Assign it to me under JWoC

[SharonIV0x86]

@SharonIV0x86
Assign it to me under JWoC

Assigned. You can start working on it.