Changed test_query_eval to use pytest fixtures

[demianw]

addressing issue #69

[demianw]

@jhlegarreta do you want to check this PR fixing the test issue #69 ?

[jhlegarreta]

@demianw I have checkout the branch and ran ppytest on the file 100 times 4 times using the pytest-repeat package; first time all passed, next three times, it failed:

Passed:

Failed:

Failed:

So the change does not fix the issue. Feel free to merge it if you believe it constitutes an improvement anyways or if you think it will allow debugging this better.

[demianw]

Thanks for the insight. I will test with pytest-repeat as you recommended.