This was not an issue with pdo_dblib, but rather with FreeTDS. FreeTDS has been
fixed as of the fc820490336c50d5c175d2a15327383256add4c9 on that repo. These
tests will be skipped if a version of FreeTDS with that issue is present.
I only cleaned up this commit for pushing. For fixing the FreeTDS issue and
writing corresponding pdo_dblib tests, thanks to:
Jeff Farr <jefarr@wayfair.com>