Fix condor driver without shared filesystem

This closes ATLASG-2563 fixing the problem when running without a shared filesystem (see jira).

• Don't use /tmp: there is no reason to use /tmp when running condor, actually, it is quite bad. Condor guarantees that the working directory on the worker node has the specified requirement (this is not true for /tmp). This also fix the bug explained in the jira, due to inconsistent paths.
• Move to cpack to create the tarball. I guess this was suggested by @akraszna (email to hn-atlas-PATHelp@cern.ch Sep 6, 2021). I am not an expert, I tried to get a tarball identical to the previous one. I am using

pack -D CPACK_INSTALL_PREFIX=. -G TGZ --config $TestArea/CPackConfig.cmake

To make the same filename as before (and to make it easily predictable) I am renaming it with

mv_command << "mv WorkDir_" << std::getenv("WorkDir_VERSION") << "_" << std::getenv("WorkDir_PLATFORM") << ".tar.gz " << tarballName;

Probably there is a better way to do it. I have noticed cpack is quite slower than tar

Unfortunately, I have to modify BatchDriver.cxx which is in common with many other batch drivers, but I have no access to any of them, so I can't test if this change affects others. I guess @krumnack has an opinion.