Refactor GraphTraversalService Implementation

[yashTEF]

The existing findShortestPath() implementation for GraphTraversalService is cumbersome and hard to read, hence it can be refactored and implemented in a shorter and more efficient manner.

[orende]

@yashTEF The code changes look good to me, but for the sake of verifying that no regressions have been introduced, would you mind adding a unit test for the GraphTraversalService class?

[yashTEF]

@orende , there already seems to be a unit test present which tests the correctness of possible routes obtained from findShortestPath in the ExternalRoutingServiceTest class under the testCalculatePossibleRoutes() method.

Is this what you are referring to?

[yashTEF]

@orende , there already seems to be a unit test present which tests the correctness of possible routes obtained from findShortestPath in the ExternalRoutingServiceTest class under the testCalculatePossibleRoutes() method.

Is this what you are referring to?

@orende Any update, Is the above mentioned unit test sufficient or some other unit test needs to be added?

[orende]

@yashTEF Sorry about the late response. I looked at ExternalRoutingServiceTest and you're right in that it covers the functionality.