Set the cache directory for com.apple.dt.instruments

There are a number of test machines on our CI farm. I've noticed the Mac machines have started to run out of disk space. This is caused by the directory

/Library/Caches/com.apple.dt.instruments

Obviously the tests are causing this growth. Is it possible for me to redirect them to create the cache in our Jenkins workspace? i.e. So the cache will be deleted between runs.