Fix test coverage upload

[KyleJune]

My previous PR #95 added a few test files that had no tests in them. despite having fail_ci_if_error set to true, it is failing with an unknown error.

https://app.codecov.io/github/udibo/react-app/commit/3b82a7fada671228654a6f8dfeb60b8322e54d74

I suspect it is related to the files not actually having any test cases but I'm not sure. The deno coverage command seems to be able to handle the generated coverage just fine but maybe there is an issue with the generated cov files that codecov uses.

[KyleJune]

Nevermind, it looks like maybe the issue was on codecov's side because that link now shows that the upload was successful. It was showing an unknown error previously. I'm guessing they retried processing it and it worked.