don't migrate test config files upon load

[tarheel]

If you open any config with version = TEST in the UI, you get a message like this:

2020-04-22 10:34:36 PDT INFO: Migrated tabulator config version from TEST to 1.1.0.

And then you have to save the changes in order to run the tabulation.

We should just not do this when version = TEST.