As we are hiding successfully matched rows, in the case of all rows were matched there is nothing to display, so displaying just the table header would lead the user to wrong interpretation of results as we [discussed earlier](https://github.com/dbfit/dbfit/pull/203#discussion_r8830783), so a summary was added to advise that no errors were found.

When matching fails the behavior is exactly the same as `ComparedStoredQueries`, so the summary is not needed.