SERVER-9941 Always link client tests against client library in 'sharedclient' directory

Otherwise, we end up with a link dependency into the build dir, which makes it impossible
to run smoke.py if you don't have a build directory around anymore, for some reason
(cherry picked from commit 6e15f4f8f462aab68e59d042413a9a93e5851b0f)
SERVER-9942 Give shared client tests a unique name to placate buildlogger
(cherry picked from commit af07d274c2dc0806966b2ffc991eb120ca232da1)