connmgr-unit-test: Use iotable

This wasn't part of cmake and thus I missed it when checking against the
codebase. This commit fixes the build issues found

Change-Id: I6424d4d428de03eb094a1b16331c515fa9a7014e
Reviewed-on: http://review.couchbase.org/33581
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>