Add coverage reporting to CI

[damithc]

Problem: We had to drop Coveralls support when we moved from Travis to GitHub Actions.

Suggestion: We can add some kind of coverage reporting to CI.

[seanlowjk]

Bumping the issue here, I feel that it possible that we can explore the use of Coveralls with Github Actions here

It is pretty to set up and we are still able to get the coverage report as such from Coveralls.

If possible, is it alright if I investigate and find out more how to set this up?

[damithc]

Looks like at some point we adopted CodeCov for coverage reporting purposes. So, the decision now is if coveralls is better than codecov. Sure, you can investigate @seanlowjk

[fzdy1914]

If I remember correctly, coverall is deprecated because the Gradle plugin we are using is not being updated anymore, and using CodeCov, there is no need for a plugin there.

[seanlowjk]

Based on the forums and my own trying of both, I feel that CodeCov's reports are easier to understand and that is crucial for students taking this module who have their first experience with software testing.

As a result, it would be better to go with Codecov!