Bamboo should provide a separate tmp directory for each build

This would solve problems like https://extranet.atlassian.com/jira/browse/ADM-3995 - 2 agents running on single machine, both running a unit test that creates a temporary file with the same name.

Such per-build directory might be cleaned up after the build is finished, to solve faulty test which use repeatable names and fail to clean up in some cases.