Don't test Rails 5.2.0.rc2 on MRI 2.2.10.
Don't test Rails 5.2.0.rc2 on MRI 2.2.10.

The version check in Rails wasn't done right (though the next release has a fix), as it thinks 2.2.10 is older than 2.2.2.

pat/thinking-sphinx,pat/thinking-sphinx