Fix circleci timing

[brittonsmith]

PR Summary

This is a test to temporarily run all test on a single test runner in circleci. The hope is that this will get rid of the errors about no prior testing data existing for certain tests. My suspicion is that data from multiple runners is not being recombined.

PR Checklist

• [ ] Code passes tests.
• [ ] New features are documented with docstrings and narrative docs.
• [ ] Tests added for fixed bugs or new features.

[brittonsmith]

Never mind. The issue is with how the file names are reported by pytest. Pytest reports most of the file as being yt/utilities/testing.py because that is where the methods in the base class are defined. I can't find any way to make it report actual test file (i.e., the file being loaded by pytest) instead of the module location of the test function. We'll have to leave things the way they are for now. I'll try one more thing then leave it.

[brittonsmith]

circleci will split by classnames, which would give the correct distinction between the various classes, but pytest cannot run with this input. A workaround will probably require some custom code to calculate timings based on classname or testname and then output the appropriate files.